| Commission  | Name of Registrant, State of Incorporation,                 | IRS Employer          |
|-------------|-------------------------------------------------------------|-----------------------|
| File Number | Address of Principal Executive Offices and Telephone Number | Identification Number |
| 1-9894      | ALLIANT ENERGY CORPORATION                                  | 39-1380265            |
|        | (a Wisconsin corporation)                                   |                  |
|        | 4902 N. Biltmore Lane                                       |                  |
|        | Madison, Wisconsin 53718                                    |                  |
|        | Telephone (608)458-3311                                     |                  |
|        |                                                        |                  |
| 0-4117-1    | INTERSTATE POWER AND LIGHT COMPANY                          | 42-0331370            |
|        | (an Iowa corporation)                                       |                  |
|        | Alliant Energy Tower                                        |                  |
|        | Cedar Rapids, Iowa 52401                                    |                  |
|        | Telephone (319)786-4411                                     |                  |
|        |                                                        |                  |
| 0-337       | WISCONSIN POWER AND LIGHT COMPANY                           | 39-0714890            |
|        | (a Wisconsin corporation)                                   |                  |
|        | 4902 N. Biltmore Lane                                       |                  |
|        | Madison, Wisconsin 53718                                    |                  |
|        | Telephone (608)458-3311                                     |                  |

|                               |        |        |            | Smaller   |
|------------------------------------|-------------|-------------|-----------------|-----------|
|                               | Large       |        |            | Reporting |
|                               | Accelerated | Accelerated | Non-accelerated | Company   |
|                               | Filer       | Filer       | Filer           | Filer     |
| Alliant Energy Corporation         | [X]         |        |            |      |
| Interstate Power and Light Company |        |        | [X]             |      |
| Wisconsin Power and Light Company  |        |        | [X]             |      |

----

| Alliant Energy Corporation         | Common stock, $0.01 par value, 110,634,276 shares outstanding               |
|------------------------------------|-----------------------------------------------------------------------------|
| Interstate Power and Light Company | Common stock, $2.50 par value, 13,370,788 shares outstanding (all of which  |
|                               | are owned beneficially and of record by Alliant Energy Corporation)         |
| Wisconsin Power and Light Company  | Common stock, $5 par value, 13,236,601 shares outstanding (all of which are |
|                               | owned beneficially and of record by Alliant Energy Corporation)             |

|     | TABLE OF CONTENTS                                                                                      | Page   |
|----------|--------------------------------------------------------------------------------------------------------|--------|
|     |                                                                                                   |   |
|     | Forward-looking Statements                                                                             | 1      |
| Part I.  | Financial Information                                                                                  | 3      |
| Item 1.  | Condensed Consolidated Financial Statements (Unaudited)                                                | 3      |
|     | Alliant Energy Corporation:                                                                            |   |
|     | Condensed Consolidated Statements of Income for the Three and Nine Months Ended Sep. 30, 2009 and 2008 | 3      |
|     | Condensed Consolidated Balance Sheets as of Sep. 30, 2009 and Dec. 31, 2008                            | 4      |
|     | Condensed Consolidated Statements of Cash Flows for the Nine Months Ended Sep. 30, 2009 and 2008       | 6      |
|     | Notes to Condensed Consolidated Financial Statements                                                   | 7      |
|     | Interstate Power and Light Company:                                                                    |   |
|     | Condensed Consolidated Statements of Income for the Three and Nine Months Ended Sep. 30, 2009 and 2008 | 35     |
|     | Condensed Consolidated Balance Sheets as of Sep. 30, 2009 and Dec. 31, 2008                            | 36     |
|     | Condensed Consolidated Statements of Cash Flows for the Nine Months Ended Sep. 30, 2009 and 2008       | 38     |
|     | Notes to Condensed Consolidated Financial Statements                                                   | 39     |
|     | Wisconsin Power and Light Company:                                                                     |   |
|     | Condensed Consolidated Statements of Income for the Three and Nine Months Ended Sep. 30, 2009 and 2008 | 42     |
|     | Condensed Consolidated Balance Sheets as of Sep. 30, 2009 and Dec. 31, 2008                            | 43     |
|     | Condensed Consolidated Statements of Cash Flows for the Nine Months Ended Sep. 30, 2009 and 2008       | 45     |
|     | Notes to Condensed Consolidated Financial Statements                                                   | 46     |
| Item 2.  | Management’s Discussion and Analysis of Financial Condition and Results of Operations            | 49     |
| Item 3.  | Quantitative and Qualitative Disclosures About Market Risk                                             | 87     |
| Item 4.  | Controls and Procedures                                                                                | 87     |
| Part II. | Other Information                                                                                      | 87     |
| Item 1.  | Legal Proceedings                                                                                      | 87     |
| Item 1A. | Risk Factors                                                                                           | 87     |
| Item 2.  | Unregistered Sales of Equity Securities and Use of Proceeds                                            | 88     |
| Item 6.  | Exhibits                                                                                               | 88     |
|     | Signatures                                                                                             | 89     |

----

| ·   | federal and state regulatory or governmental actions, including the impact of energy-related and tax legislation and of regulatory agency orders; |
|--------------------|---------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | their ability to obtain adequate and timely rate relief to allow for, among other things, the recovery of operating costs, deferred expenditures and capital expenditures, including any construction costs incurred over the predetermined level included in the advanced rate making principles for IPL’s Whispering Willow - East wind project, costs relatedto generating units that may be permanently closed, the earning of reasonable rates of return, and the payment of expected levels of dividends; |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | the state of the economy in their service territories and resulting implications on sales, margins and ability to collect unpaid bills, in particular as a result of the recession; |
|--------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | weather effects on results of operations; |
|--------------------|-------------------------------------------|

| ·   | developments that adversely impact their ability to implement their strategic plans including unanticipated issues in connection with construction of their new wind generating facilities, WPL’s potential purchase of the Riverside Energy Center (Riverside), and unfavorable regulatory outcomes; |
|--------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | IPL’s ability to reduce the impact of transmission rate increases for 2009 and future years, either through regulatory proceedings with the Federal Energy Regulatory Commission (FERC) or by recovery of costs in rates; |
|--------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | issues related to the availability of generating facilities and the supply and delivery of fuel and purchased electricity and price thereof, including the ability to recover and to retain the recovery of purchased power, fuel and fuel-related costs through rates in a timely manner; |
|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | the impact that fuel and fuel-related prices and other economic conditions may have on their customers’ demand for utility services; |
|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | impacts that storms or natural disasters in their service territories may have on their operations and rate relief for costs associated with restoration activities; |
|--------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | issues associated with environmental remediation efforts and with environmental compliance generally, including changing environmental laws and regulations, the ability to defend against environmental claims brought by state and federal agencies or third parties such as the Sierra Club, and the ability to recover through rates all environmental compliancecosts, including costs for projects put on hold due to uncertainty of future environmental laws and regulations; |
|--------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | potential impacts of any future laws or regulations regarding global climate change or carbon emissions reductions, including the American Clean Energy and Security Act, which contains a proposed greenhouse gas (GHG) cap-and-trade program; |
|--------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | the growth rate of ethanol and biodiesel production in their service territories; |
|--------------------|-----------------------------------------------------------------------------------|

| ·   | continued access to the capital markets on competitive terms and rates; |
|--------------------|-------------------------------------------------------------------------|

| ·   | financial impacts of risk hedging strategies, including the impact of weather hedges or the absence of weather hedges on earnings; |
|--------------------|------------------------------------------------------------------------------------------------------------------------------------|

| ·   | sales and project execution for RMT, Inc. (RMT), the level of growth in the wind development market and the impact of the American Recovery and Reinvestment Act of 2009 (ARRA) and pending legislation; |
|--------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | issues related to electric transmission, including operating in the Midwest Independent Transmission System Operator (MISO) energy and ancillary services markets, the impacts of potential future billing adjustments from MISO and recovery of costs incurred; |
|--------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | unplanned outages at generating facilities and risks related to recovery of resulting incremental costs through rates; |
|--------------------|------------------------------------------------------------------------------------------------------------------------|

| ·   | Alliant Energy’s ability to successfully defend against, and any liabilities arising out of, the purported shareowner derivative complaint stemming from the Exchangeable Senior Notes due 2030 litigation; |
|--------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | Alliant Energy’s ability to successfully defend against, and any liabilities arising out of, the alleged violation of the Employee Retirement Income Security Act of 1974 by Alliant Energy’s Cash Balance Pension Plan; |
|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | IPL’s ability to successfully resolve the dispute with the parties to the joint operating agreement for Sutherland #4; |
|--------------------|------------------------------------------------------------------------------------------------------------------------------|

| ·   | current or future litigation, regulatory investigations, proceedings or inquiries; |
|--------------------|------------------------------------------------------------------------------------|

| ·   | Alliant Energy’s ability to sustain its dividend payout ratio goal; |
|--------------------|---------------------------------------------------------------------------|

| ·   | the direct or indirect effects resulting from terrorist incidents or responses to such incidents; |
|--------------------|---------------------------------------------------------------------------------------------------|

----

| ·   | employee workforce factors, including changes in key executives, collective bargaining agreements, work stoppages or additional restructurings; |
|--------------------|-------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | access to technological developments; |
|--------------------|---------------------------------------|

| ·   | any material post-closing adjustments related to any of their past asset divestitures; |
|--------------------|----------------------------------------------------------------------------------------|

| ·   | the impact of necessary accruals for the terms of incentive compensation plans; |
|--------------------|---------------------------------------------------------------------------------|

| ·   | the effect of accounting pronouncements issued periodically by standard-setting bodies; |
|--------------------|-----------------------------------------------------------------------------------------|

| ·   | the ability to continue cost controls and operational efficiencies; |
|--------------------|---------------------------------------------------------------------|

| ·   | increased retirement plan costs due to decreases in the market value of retirement plan assets; |
|--------------------|-------------------------------------------------------------------------------------------------|

| ·   | the ability to utilize tax capital losses and net operating losses generated to date, and those that may be generated in the future, before they expire; |
|--------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | the ability to successfully complete ongoing tax audits and appeals with no material impact on earnings and cash flows; |
|--------------------|-------------------------------------------------------------------------------------------------------------------------|

| ·   | inflation and interest rates; and |
|--------------------|-----------------------------------|

| ·   | factors listed in Item 1A Risk Factors and “Other Matters - Other Future Considerations” in Management’s Discussion and Analysis of Financial Condition and Results of Operations. |
|--------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

|   PART I. FINANCIAL INFORMATION ITEM 1. CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED) ALLIANT ENERGY CORPORATIONCONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)  |   |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------|
|                                                                                                                                                                                                        |   | For the Three Months |   |   | For the Nine Months |   |
|                                                                                                                                                                                                        |   | Ended September 30, |   |   | Ended September 30, |   |
|                                                                                                                                                                                                        |   | 2009 |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |
|                                                                                                                                                                                                        |   | (dollars in millions, except per share amounts) |   |
| Operating revenues:                                                                                                                                                                                         |   |   |   |   |   |   |   |   |   |   |   |   |
|   Utility:                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |
|     Electric                                                                                                                                                                            |   | $ | 725.3 |   |   | $ | 714.0 |   |   | $ | 1,901.2 |   |   | $ | 1,858.4 |   |
|     Gas                                                                                                                                                                                 |   |   | 39.1 |   |   |   | 73.5 |   |   |   | 361.8 |   |   |   | 503.1 |   |
|     Other                                                                                                                                                                               |   |   | 20.1 |   |   |   | 30.8 |   |   |   | 69.4 |   |   |   | 64.3 |   |
|   Non-regulated                                                                                                                                                                                   |   |   | 101.2 |   |   |   | 162.0 |   |   |   | 245.5 |   |   |   | 373.9 |   |
|                                                                                                                                                                                                        |   |   | 885.7 |   |   |   | 980.3 |   |   |   | 2,577.9 |   |   |   | 2,799.7 |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating expenses:                                                                                                                                                                                         |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|   Utility:                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|     Electric production fuel and purchased power                                                                                                                                        |   |   | 336.3 |   |   |   | 317.2 |   |   |   | 922.9 |   |   |   | 876.3 |   |
|     Electric transmission service                                                                                                                                                       |   |   | 55.1 |   |   |   | 49.2 |   |   |   | 172.1 |   |   |   | 139.3 |   |
|     Cost of gas sold                                                                                                                                                                    |   |   | 13.9 |   |   |   | 46.9 |   |   |   | 240.5 |   |   |   | 365.8 |   |
|     Other operation and maintenance                                                                                                                                                     |   |   | 130.0 |   |   |   | 151.3 |   |   |   | 437.3 |   |   |   | 442.6 |   |
|   Non-regulated operation and maintenance                                                                                                                                                         |   |   | 95.7 |   |   |   | 141.5 |   |   |   | 230.7 |   |   |   | 318.8 |   |
|   Depreciation and amortization                                                                                                                                                                   |   |   | 69.9 |   |   |   | 57.9 |   |   |   | 201.7 |   |   |   | 181.2 |   |
|   Taxes other than income taxes                                                                                                                                                                   |   |   | 24.9 |   |   |   | 25.8 |   |   |   | 76.3 |   |   |   | 78.1 |   |
|                                                                                                                                                                                                        |   |   | 725.8 |   |   |   | 789.8 |   |   |   | 2,281.5 |   |   |   | 2,402.1 |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating income                                                                                                                                                                                            |   |   | 159.9 |   |   |   | 190.5 |   |   |   | 296.4 |   |   |   | 397.6 |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Interest expense and other:                                                                                                                                                                                 |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|   Interest expense                                                                                                                                                                                |   |   | 42.4 |   |   |   | 30.0 |   |   |   | 113.8 |   |   |   | 90.0 |   |
|   Loss on early extinguishment of debt                                                                                                                                                            |   |   | 202.8 |   |   |   | - |   |   |   | 202.8 |   |   |   | - |   |
|   Equity income from unconsolidated investments, net                                                                                                                                              |   |   | (9.5 | ) |   |   | (9.6 | ) |   |   | (27.3 | ) |   |   | (24.3 | ) |
|   Allowance for funds used during construction                                                                                                                                                    |   |   | (13.9 | ) |   |   | (8.4 | ) |   |   | (34.7 | ) |   |   | (15.8 | ) |
|   Interest income and other                                                                                                                                                                       |   |   | (1.0 | ) |   |   | (2.8 | ) |   |   | (4.1 | ) |   |   | (14.1 | ) |
|                                                                                                                                                                                                        |   |   | 220.8 |   |   |   | 9.2 |   |   |   | 250.5 |   |   |   | 35.8 |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Income (loss) from continuing operations before income taxes                                                                                                                                                |   |   | (60.9 | ) |   |   | 181.3 |   |   |   | 45.9 |   |   |   | 361.8 |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Income tax expense (benefit)                                                                                                                                                                                |   |   | (22.2 | ) |   |   | 67.6 |   |   |   | (26.5 | ) |   |   | 118.8 |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Income (loss) from continuing operations, net of tax                                                                                                                                                        |   |   | (38.7 | ) |   |   | 113.7 |   |   |   | 72.4 |   |   |   | 243.0 |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Income (loss) from discontinued operations, net of tax                                                                                                                                                      |   |   | (1.0 | ) |   |   | (0.6 | ) |   |   | (1.0 | ) |   |   | 8.4 |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Net income (loss)                                                                                                                                                                                           |   |   | (39.7 | ) |   |   | 113.1 |   |   |   | 71.4 |   |   |   | 251.4 |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Preferred dividend requirements of subsidiaries                                                                                                                                                             |   |   | 4.6 |   |   |   | 4.6 |   |   |   | 14.0 |   |   |   | 14.0 |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Net income (loss) attributable to Alliant Energy common shareowners                                                                                                                                         |   | $ | (44.3 | ) |   | $ | 108.5 |   |   | $ | 57.4 |   |   | $ | 237.4 |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Weighted average number of common shares                                                                                                                                                                    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|    outstanding (basic) (000s)                                                                                                                                                                |   |   | 110,288 |   |   |   | 110,182 |   |   |   | 110,257 |   |   |   | 110,166 |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Weighted average number of common shares                                                                                                                                                                    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|    outstanding (diluted) (000s)                                                                                                                                                              |   |   | 110,288 |   |   |   | 110,313 |   |   |   | 110,340 |   |   |   | 110,313 |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Earnings per weighted average common share attributable to                                                                                                                                                  |   |   |   |   |   |   |   |   |   |
|   Alliant Energy common shareowners (basic and diluted):                                                                                                                                               |   |   |   |   |   |   |   |   |   |   |   |   |   |
|    Income (loss) from continuing operations, net of tax                                                                                                                                      |   | $ | (0.39 | ) |   | $ | 0.99 |   |   | $ | 0.53 |   |   | $ | 2.08 |   |
|    Income (loss) from discontinued operations, net of tax                                                                                                                                    |   |   | (0.01 | ) |   |   | (0.01 | ) |   |   | (0.01 | ) |   |   | 0.07 |   |
|    Net income (loss) attributable to Alliant Energy common shareowners                                                                                                                       |   | $ | (0.40 | ) |   | $ | 0.98 |   |   | $ | 0.52 |   |   | $ | 2.15 |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|   Amounts attributable to Alliant Energy common shareowners:                                                                                                                                           |   |   |   |   |   |   |   |   |   |
|    Income (loss) from continuing operations, net of tax                                                                                                                                      |   | $ | (43.3 | ) |   | $ | 109.1 |   |   | $ | 58.4 |   |   | $ | 229.0 |   |
|    Income (loss) from discontinued operations, net of tax                                                                                                                                    |   |   | (1.0 | ) |   |   | (0.6 | ) |   |   | (1.0 | ) |   |   | 8.4 |   |
|    Net income (loss) attributable to Alliant Energy common shareowners                                                                                                                       |   | $ | (44.3 | ) |   | $ | 108.5 |   |   | $ | 57.4 |   |   | $ | 237.4 |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Dividends declared per common share                                                                                                                                                                         |   | $ | 0.375 |   |   | $ | 0.35 |   |   | $ | 1.125 |   |   | $ | 1.05 |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                                                                                                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these statements.                                                                                             |   |

----

| ALLIANT ENERGY CORPORATION                                                                                                 |   |
|----------------------------------------------------------------------------------------------------------------------------|--------|
| CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)                                                                          |   |
|                                                                                                                       |   |   |   |   |   |   |
|                                                                                                                       |   | September 30, |   |   | December 31, |   |
| ASSETS                                                                                                                     |   | 2009 |   |   | 2008 |   |
|                                                                                                                       |   | (in millions) |   |
| Property, plant and equipment:                                                                                             |   |   |   |   |   |   |
|   Utility:                                                                                                       |   |   |   |   |   |   |
|     Electric plant in service                                                                          |   | $ | 6,560.8 |   |   | $ | 6,018.8 |   |
|     Gas plant in service                                                                               |   |   | 785.5 |   |   |   | 761.6 |   |
|     Other plant in service                                                                             |   |   | 518.4 |   |   |   | 481.0 |   |
|     Accumulated depreciation                                                                           |   |   | (2,940.7 | ) |   |   | (2,766.2 | ) |
|         Net plant                                                                  |   |   | 4,924.0 |   |   |   | 4,495.2 |   |
|     Construction work in progress:                                                                     |   |   |   |   |   |   |   |   |
|         Whispering Willow - East wind project (Interstate Power and Light Company) |   |   | 432.0 |   |   |   | 189.4 |   |
|         Bent Tree wind project (Wisconsin Power and Light Company)                 |   |   | 124.3 |   |   |   | - |   |
|         Other                                                                      |   |   | 231.9 |   |   |   | 294.2 |   |
|     Other, less accumulated depreciation                                                               |   |   | 45.0 |   |   |   | 22.4 |   |
|           Total utility                                                  |   |   | 5,757.2 |   |   |   | 5,001.2 |   |
|   Non-regulated and other:                                                                                       |   |   |   |   |   |   |   |   |
|     Non-regulated Generation, less accumulated depreciation                                            |   |   | 134.5 |   |   |   | 230.1 |   |
|     Alliant Energy Corporate Services, Inc. and other, less accumulated depreciation                   |   |   | 146.1 |   |   |   | 122.2 |   |
|           Total non-regulated and other                                  |   |   | 280.6 |   |   |   | 352.3 |   |
|                                                                                                                       |   |   | 6,037.8 |   |   |   | 5,353.5 |   |
|                                                                                                                       |   |   |   |   |   |   |   |   |
|                                                                                                                       |   |   |   |   |   |   |   |   |
| Current assets:                                                                                                            |   |   |   |   |   |   |   |   |
|   Cash and cash equivalents                                                                                      |   |   | 176.7 |   |   |   | 346.9 |   |
|   Accounts receivable:                                                                                           |   |   |   |   |   |   |   |   |
|     Customer, less allowance for doubtful accounts                                                     |   |   | 170.6 |   |   |   | 233.9 |   |
|     Unbilled utility revenues                                                                          |   |   | 131.4 |   |   |   | 186.2 |   |
|     Other, less allowance for doubtful accounts                                                        |   |   | 74.5 |   |   |   | 138.6 |   |
|   Income tax refunds receivable                                                                                  |   |   | 202.2 |   |   |   | 67.7 |   |
|   Production fuel, at weighted average cost                                                                      |   |   | 139.4 |   |   |   | 111.7 |   |
|   Materials and supplies, at weighted average cost                                                               |   |   | 54.8 |   |   |   | 55.8 |   |
|   Gas stored underground, at weighted average cost                                                               |   |   | 50.3 |   |   |   | 75.0 |   |
|   Regulatory assets                                                                                              |   |   | 119.7 |   |   |   | 101.6 |   |
|   Derivative assets                                                                                              |   |   | 23.4 |   |   |   | 18.1 |   |
|   Other                                                                                                          |   |   | 91.4 |   |   |   | 110.1 |   |
|                                                                                                                       |   |   | 1,234.4 |   |   |   | 1,445.6 |   |
|                                                                                                                       |   |   |   |   |   |   |   |   |
|                                                                                                                       |   |   |   |   |   |   |   |   |
| Investments:                                                                                                               |   |   |   |   |   |   |   |   |
|   Investment in American Transmission Company LLC                                                                |   |   | 211.8 |   |   |   | 195.1 |   |
|   Other                                                                                                          |   |   | 63.2 |   |   |   | 60.9 |   |
|                                                                                                                       |   |   | 275.0 |   |   |   | 256.0 |   |
|                                                                                                                       |   |   |   |   |   |   |   |   |
|                                                                                                                       |   |   |   |   |   |   |   |   |
| Other assets:                                                                                                              |   |   |   |   |   |   |   |   |
|   Regulatory assets                                                                                              |   |   | 1,029.5 |   |   |   | 933.1 |   |
|   Deferred charges and other                                                                                     |   |   | 179.0 |   |   |   | 213.3 |   |
|                                                                                                                       |   |   | 1,208.5 |   |   |   | 1,146.4 |   |
|                                                                                                                       |   |   |   |   |   |   |   |   |
|                                                                                                                       |   |   |   |   |   |   |   |   |
| Total assets                                                                                                               |   | $ | 8,755.7 |   |   | $ | 8,201.5 |   |
|                                                                                                                       |   |   |   |   |   |   |   |   |
|                                                                                                                       |   |   |   |   |   |   |   |   |
| The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these statements.            |   |

----

| ALLIANT ENERGY CORPORATION                                                                                      |   |
|-----------------------------------------------------------------------------------------------------------------|--------|
| CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Continued)                                                   |   |
|                                                                                                            |   |   |   |   |   |   |
|                                                                                                            |   | September 30, |   |   | December 31, |   |
| CAPITALIZATION AND LIABILITIES                                                                                  |   | 2009 |   |   | 2008 |   |
|                                                                                                            |   | (in millions, except per |   |
|                                                                                                            |   | share and share amounts) |   |
| Capitalization:                                                                                                 |   |   |   |   |   |   |
|   Alliant Energy Corporation common equity:                                                           |   |   |   |   |   |   |
|     Common stock - $0.01 par value - authorized 240,000,000 shares;                              |   |   |   |   |
|       110,634,276 and 110,449,099 shares outstanding                              |   | $ | 1.1 |   |   | $ | 1.1 |   |
|     Additional paid-in capital                                                              |   |   | 1,498.1 |   |   |   | 1,494.9 |   |
|     Retained earnings                                                                       |   |   | 1,269.5 |   |   |   | 1,336.2 |   |
|     Accumulated other comprehensive loss                                                    |   |   | (1.0 | ) |   |   | (1.4 | ) |
|     Shares in deferred compensation trust - 262,428 and 238,241 shares                           |   |   |   |   |   |
|       at a weighted average cost of $30.37 and $30.79 per share                   |   |   | (8.0 | ) |   |   | (7.3 | ) |
|          Total Alliant Energy Corporation common equity            |   |   | 2,759.7 |   |   |   | 2,823.5 |   |
|   Cumulative preferred stock of Interstate Power and Light Company                                    |   |   | 183.8 |   |   |   | 183.8 |   |
|   Noncontrolling interest                                                                             |   |   | 2.1 |   |   |   | 2.1 |   |
|          Total equity                                              |   |   | 2,945.6 |   |   |   | 3,009.4 |   |
|   Cumulative preferred stock of Wisconsin Power and Light Company                                     |   |   | 60.0 |   |   |   | 60.0 |   |
|   Long-term debt, net (excluding current portion)                                                     |   |   | 2,155.9 |   |   |   | 1,748.3 |   |
|                                                                                                            |   |   | 5,161.5 |   |   |   | 4,817.7 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Current liabilities:                                                                                            |   |   |   |   |   |   |   |   |
|   Current maturities of long-term debt                                                                |   |   | 101.5 |   |   |   | 136.4 |   |
|   Commercial paper                                                                                    |   |   | - |   |   |   | 86.1 |   |
|   Other short-term borrowings                                                                         |   |   | 170.0 |   |   |   | - |   |
|   Accounts payable                                                                                    |   |   | 328.1 |   |   |   | 425.1 |   |
|   Regulatory liabilities                                                                              |   |   | 100.1 |   |   |   | 101.9 |   |
|   Accrued taxes                                                                                       |   |   | 38.9 |   |   |   | 52.5 |   |
|   Derivative liabilities                                                                              |   |   | 94.1 |   |   |   | 78.6 |   |
|   Other                                                                                               |   |   | 160.1 |   |   |   | 157.6 |   |
|                                                                                                            |   |   | 992.8 |   |   |   | 1,038.2 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Other long-term liabilities and deferred credits:                                                               |   |   |   |   |   |   |   |   |
|   Deferred income taxes                                                                               |   |   | 1,132.1 |   |   |   | 971.2 |   |
|   Regulatory liabilities                                                                              |   |   | 707.2 |   |   |   | 637.9 |   |
|   Pension and other benefit obligations                                                               |   |   | 469.4 |   |   |   | 513.9 |   |
|   Other                                                                                               |   |   | 292.7 |   |   |   | 222.6 |   |
|                                                                                                            |   |   | 2,601.4 |   |   |   | 2,345.6 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Total capitalization and liabilities                                                                            |   | $ | 8,755.7 |   |   | $ | 8,201.5 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these statements. |   |

----

|  ALLIANT ENERGY CORPORATION                                                                                |   |
|-----------------------------------------------------------------------------------------------------------------|--------|
| CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)                                                     |   |
|                                                                                                            |   |   |   |   |   |   |
|                                                                                                            |   | For the Nine Months Ended September 30, |   |
|                                                                                                            |   | 2009 |   |   | 2008 |   |
|                                                                                                            |   | (in millions) |   |
| Cash flows from operating activities:                                                                           |   |   |   |   |   |   |
|   Net income                                                                                          |   | $ | 71.4 |   |   | $ | 251.4 |   |
|   Adjustments to reconcile net income to net cash flows from operating activities:                         |   |
|     Depreciation and amortization                                                           |   |   | 201.7 |   |   |   | 181.2 |   |
|     Other amortizations                                                                     |   |   | 32.9 |   |   |   | 34.8 |   |
|     Deferred tax expense and investment tax credits                                         |   |   | 88.5 |   |   |   | 4.2 |   |
|     Loss on early extinguishment of debt                                                    |   |   | 202.8 |   |   |   | - |   |
|     Equity income from unconsolidated investments, net                                      |   |   | (27.3 | ) |   |   | (24.3 | ) |
|     Distributions from equity method investments                                            |   |   | 22.4 |   |   |   | 20.9 |   |
|     Equity component of allowance for funds used during construction                        |   |   | (26.9 | ) |   |   | (10.7 | ) |
|     Other                                                                                   |   |   | 8.7 |   |   |   | 9.5 |   |
|   Other changes in assets and liabilities:                                                            |   |   |   |   |   |   |   |   |
|     Accounts receivable                                                                     |   |   | 139.5 |   |   |   | (26.2 | ) |
|     Sale of accounts receivable                                                             |   |   | 35.0 |   |   |   | 50.0 |   |
|     Income tax refunds receivable                                                           |   |   | (134.5 | ) |   |   | 7.8 |   |
|     Production fuel                                                                         |   |   | (27.7 | ) |   |   | (15.6 | ) |
|     Gas stored underground                                                                  |   |   | 24.7 |   |   |   | (13.3 | ) |
|     Regulatory assets                                                                       |   |   | (147.7 | ) |   |   | (32.0 | ) |
|     Prepaid gas costs                                                                       |   |   | 18.1 |   |   |   | (12.5 | ) |
|     Accounts payable                                                                        |   |   | (57.2 | ) |   |   | 45.3 |   |
|     Regulatory liabilities                                                                  |   |   | 78.7 |   |   |   | (24.6 | ) |
|     Accrued taxes                                                                           |   |   | (13.6 | ) |   |   | (21.9 | ) |
|     Derivative liabilities                                                                  |   |   | 15.0 |   |   |   | 25.7 |   |
|     Deferred income taxes                                                                   |   |   | 69.7 |   |   |   | 33.1 |   |
|     Non-current taxes payable                                                               |   |   | 57.1 |   |   |   | (15.7 | ) |
|     Pension and other benefit obligations                                                   |   |   | (44.5 | ) |   |   | (2.6 | ) |
|     Accrued incentive compensation and other                                                |   |   | 3.7 |   |   |   | (49.2 | ) |
|        Net cash flows from operating activities                              |   |   | 590.5 |   |   |   | 415.3 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Cash flows used for investing activities:                                                                       |   |   |   |   |   |   |   |   |
|     Construction and acquisition expenditures:                                              |   |   |   |   |   |   |   |   |
|        Utility business                                                      |   |   | (900.2 | ) |   |   | (619.1 | ) |
|        Alliant Energy Corporate Services, Inc. and non-regulated businesses  |   |   | (44.0 | ) |   |   | (21.2 | ) |
|     Advances for customer energy efficiency projects                                        |   |   | (19.8 | ) |   |   | (17.8 | ) |
|     Collections of advances for customer energy efficiency projects                         |   |   | 53.9 |   |   |   | 32.1 |   |
|     Insurance proceeds received for property damages                                        |   |   | 37.7 |   |   |   | 3.7 |   |
|     Other                                                                                   |   |   | (10.8 | ) |   |   | 13.6 |   |
|        Net cash flows used for investing activities                          |   |   | (883.2 | ) |   |   | (608.7 | ) |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Cash flows from (used for) financing activities:                                                                |   |   |   |   |   |   |   |   |
|     Common stock dividends                                                                  |   |   | (124.1 | ) |   |   | (115.7 | ) |
|     Preferred dividends paid by subsidiaries                                                |   |   | (14.0 | ) |   |   | (14.0 | ) |
|     Proceeds from issuance of long-term debt                                                |   |   | 550.2 |   |   |   | - |   |
|     Payments for repurchase of Exchangeable Senior Notes due 2030                           |   |   | (241.2 | ) |   |   | - |   |
|     Reductions in other long-term debt                                                      |   |   | (135.8 | ) |   |   | (3.1 | ) |
|     Proceeds from borrowings under Alliant Energy's term loan facility                           |   |   | 170.0  |   |   |   | -  |   |
|     Net change in other short-term borrowings                                               |   |   | (86.1 | )  |   |   | (43.4 | ) |
|     Other                                                                                   |   |   | 3.5 |   |   |   | 3.4 |   |
|        Net cash flows from (used for) financing activities                   |   |   | 122.5 |   |   |   | (172.8 | ) |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Net decrease in cash and cash equivalents                                                                       |   |   | (170.2 | ) |   |   | (366.2 | ) |
| Cash and cash equivalents at beginning of period                                                                |   |   | 346.9 |   |   |   | 745.6 |   |
| Cash and cash equivalents at end of period                                                                      |   | $ | 176.7 |   |   | $ | 379.4 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these statements. |   |

----

|                          |   | Alliant Energy |   |   | IPL      |   |   | WPL      |   |
|-------------------------------|--------|----------------|--------|--------|----------|--------|--------|----------|--------|
|                          |   | Sep. 30,       |   |   | Dec. 31, |   |   | Sep. 30, |   |   | Dec. 31, |   |   | Sep. 30, |   |   | Dec. 31, |   |
|                          |   | 2009           |   |   | 2008     |   |   | 2009     |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |
| IPL’s base-load project |   | $              | 27.6   |   |     | $      | 30.2   |     |   | $ | 27.6 |   |   | $ | 30.2 |   |   | $ | -- |   |   | $ | -- |   |
| WPL’s base-load project |   |           | 27.1   |   |     |   | 35.6   |     |   |   | -- |   |   |   | -- |   |   |   | 27.1 |   |   |   | 35.6 |   |
| Clean air compliance projects |   |           | 18.7   |   |     |   | 20.7   |     |   |   | 9.0 |   |   |   | 12.5 |   |   |   | 9.7 |   |   |   | 8.2 |   |
| Wind projects                 |   |           | 0.9    |   |     |   | 1.4    |     |   |   | -- |   |   |   | -- |   |   |   | 0.9 |   |   |   | 1.4 |   |
|                          |   | $              | 74.3   |   |     | $      | 87.9   |     |   | $ | 36.6 |   |   | $ | 42.7 |   |   | $ | 37.7 |   |   | $ | 45.2 |   |

----

----

|                                            |   | Sep. 30, 2009 |        |   | Dec. 31, 2008 |   |
|-------------------------------------------------|--------|---------------|-------------|--------|---------------|--------|
| Total cash and cash equivalents                 |   | $             | 177         |   |          | $      | 347 |   |
| Money market fund investments                   |   | $             | 171         |   |          | $      | 339 |   |
| Interest rates on money market fund investments |   |          | 0.20 - 0.23 | %      |          |   | 1.43 - 1.83 | % |

|                       |   | Alliant Energy |   |   | IPL    |   |   | WPL    |   |
|----------------------------|--------|----------------|--------|--------|--------|--------|--------|--------|--------|
|                       |   | 2009           |   |   | 2008   |   |   | 2009   |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |
| Three Months Ended Sep. 30 |   |           |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Equity                     |   | $              | 10.8   |   |   | $      | 5.8    |   |   | $ | 9.9 |   |   | $ | 3.7 |   |   | $ | 0.9 |   |   | $ | 2.1 |   |
| Debt                       |   |           | 3.1    |   |   |   | 2.6    |   |   |   | 2.7 |   |   |   | 1.5 |   |   |   | 0.4 |   |   |   | 1.1 |   |
|                       |   | $              | 13.9   |   |   | $      | 8.4    |   |   | $ | 12.6 |   |   | $ | 5.2 |   |   | $ | 1.3 |   |   | $ | 3.2 |   |
|                       |   |           |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Nine Months Ended Sep. 30  |   |           |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Equity                     |   | $              | 26.9   |   |   | $      | 10.7   |   |   | $ | 24.9 |   |   | $ | 5.8 |   |   | $ | 2.0 |   |   | $ | 4.9 |   |
| Debt                       |   |           | 7.8    |   |   |   | 5.1    |   |   |   | 6.9 |   |   |   | 2.6 |   |   |   | 0.9 |   |   |   | 2.5 |   |
|                       |   | $              | 34.7   |   |   | $      | 15.8   |   |   | $ | 31.8 |   |   | $ | 8.4 |   |   | $ | 2.9 |   |   | $ | 7.4 |   |

----

|            |   | Three Months |   |   | Nine Months |   |
|-----------------|--------|--------------|--------|--------|-------------|--------|
|            |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| Interest income |   | $            | (1.0   | )      |        | $      | (3.5 | ) |   | $ | (3.8 | ) |   | $ | (14.7 | ) |
| Other           |   |         | --     |   |        |   | 0.7 |   |   |   | (0.3 | ) |   |   | 0.6 |   |
|            |   | $            | (1.0   | )      |        | $      | (2.8 | ) |   | $ | (4.1 | ) |   | $ | (14.1 | ) |

----

|                                        |   | 2009   |   |   | 2008   |   |
|---------------------------------------------|--------|--------|--------|--------|--------|--------|
| Cash paid (refunded) during the period for: |   |   |   |   |   |   |
| Interest, net of capitalized interest       |   | $      | 114.7  |   |   | $      | 111.3 |   |
| Income taxes, net of refunds                |   |   | (76.4  | )      |   |   | 111.7 |   |
| Noncash investing and financing activities: |   |   |   |   |   |   |   |   |
| Capital lease obligations incurred          |   |   | 5.2    |   |   |   | -- |   |

----

----

----

|                                                                |   | Three Months |   |   | Nine Months |   |
|---------------------------------------------------------------------|--------|--------------|--------|--------|-------------|--------|
|                                                                |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| Net income (loss) attributable to Alliant Energy common shareowners |   | $            | (44.3  | )      |        | $      | 108.5 |   |   | $ | 57.4 |   |   | $ | 237.4 |   |
| Unrealized holding gains (losses) on securities, net of tax         |   |         | 0.4    |   |        |   | (3.1 | ) |   |   | 0.5 |   |   |   | (0.6 | ) |
| Less:  reclassification adjustment for gains (losses)     |   |         |   |   |        |   |   |   |   |   |   |   |   |   |   |   |
| included in net income (loss), net of tax                           |   |         | --     |   |        |   | (0.3 | ) |   |   | 0.1 |   |   |   | (0.3 | ) |
| Net unrealized gains (losses) on securities, net of tax             |   |         | 0.4    |   |        |   | (2.8 | ) |   |   | 0.4 |   |   |   | (0.3 | ) |
| Pension and other postretirement benefits                           |   |         |   |   |        |   |   |   |   |   |   |   |   |   |   |   |
| amortizations, net of tax                                           |   |         | --     |   |        |   | -- |   |   |   | -- |   |   |   | 0.1 |   |
| Other comprehensive income (loss)                                   |   |         | 0.4    |   |        |   | (2.8 | ) |   |   | 0.4 |   |   |   | (0.2 | ) |
| Comprehensive income (loss)                                         |   | $            | (43.9  | )      |        | $      | 105.7 |   |   | $ | 57.8 |   |   | $ | 237.2 |   |

----

|                                            |   | Three Months |   |   | Nine Months |   |
|-------------------------------------------------|--------|--------------|--------|--------|-------------|--------|
|                                            |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| Average amount of aggregate accounts receivable |   |         |   |   |        |   |   |   |   |   |   |   |
| sold (based on daily outstanding balances)      |   | $            | 92.0   |   |        | $      | 131.1 |   |   | $ | 118.9 |   |   | $ | 58.9 |   |
| Costs incurred                                  |   |         | 0.5    |   |        |   | 1.0 |   |   |   | 1.7 |   |   |   | 1.4 |   |

|               |   | Sep. 30, 2009 |   |   | Dec. 31, 2008 |   |
|--------------------|--------|---------------|--------|--------|---------------|--------|
| WPL                |   | $             | 6      |   |          | $      | 15 |   |
| Corporate Services |   |          | --     |   |          |   | 2 |   |
| Alliant Energy     |   | $             | 6      |   |          | $      | 17 |   |

|           | Three Months |   | Nine Months |
|----------------|--------------|--------|-------------|
|           | 2009         |   | 2008        |   | 2009 |   | 2008 |
| Alliant Energy | 36.5%        |   | 37.3%       |   | (57.7%) |   | 32.8% |
| IPL            | 33.1%        |   | 33.7%       |   | 11.1% |   | 29.4% |
| WPL            | 35.4%        |   | 36.8%       |   | 33.1% |   | 36.5% |

----

----

|                                   |   | Pension Benefits |   |   | Other Postretirement Benefits |   |
|----------------------------------------|--------|------------------|--------|--------|-------------------------------|--------|
|                                   |   | Three Months     |   |   | Nine Months                   |   |   | Three Months |   |   | Nine Months |   |
|                                   |   | 2009             |   |   | 2008                          |   |   | 2009 |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |
| Service cost                           |   | $                | 3.0    |   |                          | $      | 4.1 |   |   | $ | 9.2 |   |   | $ | 12.2 |   |   | $ | 2.2 |   |   | $ | 2.1 |   |   | $ | 6.5 |   |   | $ | 6.3 |   |
| Interest cost                          |   |             | 13.6   |   |                          |   | 13.7 |   |   |   | 40.8 |   |   |   | 41.0 |   |   |   | 3.8 |   |   |   | 3.8 |   |   |   | 11.4 |   |   |   | 11.4 |   |
| Expected return on plan assets         |   |             | (11.9  | )      |                          |   | (18.7 | ) |   |   | (35.7 | ) |   |   | (56.0 | ) |   |   | (1.5 | ) |   |   | (2.3 | ) |   |   | (4.6 | ) |   |   | (6.8 | ) |
| Amortization of:                       |   |             |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Transition obligation                  |   |             | --     |   |                          |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | 0.1 |   |   |   | 0.1 |   |
| Prior service cost (credit)            |   |             | 0.6    |   |                          |   | 0.7 |   |   |   | 1.6 |   |   |   | 2.2 |   |   |   | (0.9 | ) |   |   | (0.9 | ) |   |   | (2.7 | ) |   |   | (2.7 | ) |
| Actuarial loss                         |   |             | 7.8    |   |                          |   | 1.0 |   |   |   | 23.7 |   |   |   | 3.1 |   |   |   | 1.5 |   |   |   | 0.9 |   |   |   | 4.6 |   |   |   | 2.6 |   |
| Curtailment losses (a)(b)              |   |             | --     |   |                          |   | -- |   |   |   | 1.0 |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |
| Special termination benefits costs (b) |   |             | --     |   |                          |   | -- |   |   |   | 0.5 |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |
|                                   |   | $                | 13.1   |   |                          | $      | 0.8 |   |   | $ | 41.1 |   |   | $ | 2.5 |   |   | $ | 5.1 |   |   | $ | 3.6 |   |   | $ | 15.3 |   |   | $ | 10.9 |   |

| (a)   | In 2007, members of the International Brotherhood of Electrical Workers Local 965 ratified a four-year collective bargaining agreement reached with WPL, resulting in changes to WPL’s qualified pension plan (Plan).  One of these changes provided Plan participants a one-time option to cease participating in the Plan and begin participatingin the Alliant Energy 401(k) Savings Plan with increased levels of contribution by Alliant Energy.  The election of this option did not impact a participant’s eligibility for benefits previously vested under the Plan.  In the second quarter of 2009, certain of these employees elected to cease participating in the Plan, resulting in Alliant Energy and WPL recognizing a one-time curtailment loss related to the Plan of $0.7 million for the nine months ended Sep. 30, 2009. |
|-----------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| (b)   | In the second quarter of 2009, Alliant Energy eliminated certain corporate and operations positions.  As a result, Alliant Energy recognized one-time curtailment losses and special termination benefits costs related to its pension plans of $0.3 million and $0.5 million, respectively, for the nine months ended Sep. 30, 2009. |
|-----------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

|                             |   | Alliant Energy |   |   | IPL    |   |   | WPL    |   |
|----------------------------------|--------|----------------|--------|--------|--------|--------|--------|--------|--------|
|                             |   | 2009           |   |   | 2008   |   |   | 2009   |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |
| Three Months Ended Sep. 30       |   |           |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Share-based compensation expense |   | $              | 1.3    |   |   | $      | 1.9    |   |   | $ | 0.7 |   |   | $ | 1.0 |   |   | $ | 0.6 |   |   | $ | 0.7 |   |
| Income tax benefits              |   |           | 0.5    |   |   |   | 0.8    |   |   |   | 0.3 |   |   |   | 0.5 |   |   |   | 0.2 |   |   |   | 0.3 |   |
|                             |   |           |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Nine Months Ended Sep. 30        |   |           |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Share-based compensation expense |   |           | 3.0    |   |   |   | 2.9    |   |   |   | 1.7 |   |   |   | 1.6 |   |   |   | 1.2 |   |   |   | 1.1 |   |
| Income tax benefits              |   |           | 1.2    |   |   |   | 1.2    |   |   |   | 0.7 |   |   |   | 0.7 |   |   |   | 0.5 |   |   |   | 0.4 |   |

|                        | 2009       |   | 2008       |
|-----------------------------|------------|--------|------------|
|                        | Shares (a) |   | Shares (a) |
| Nonvested shares at Jan. 1  | 208,579    |   | 221,834    |
| Granted                     | 152,735    |   | 65,516     |
| Vested                      | (84,633)   |   | (78,532)   |
| Forfeited                   | (20,102)   |   | --         |
| Nonvested shares at Sep. 30 | 256,579    |   | 208,818    |

| (a)   | Share amounts represent the target number of performance shares.  The actual number of shares that will be paid out upon vesting is dependent upon actual performance and may range from zero to 200% of the target number of shares. |
|-----------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|                                                       |   | 2009 Grant |    |   | 2008 Grant |   |   | 2007 Grant |   |
|------------------------------------------------------------|--------|------------|---------|--------|------------|--------|--------|------------|--------|
| Nonvested performance shares                               |   |       | 138,148 |   |       |   | 61,331 |       |   |   | 57,100 |   |
| Alliant Energy common stock closing price on Sep. 30, 2009 |   | $          | 27.85   |   |       | $      | 27.85  |       |   | $ | 27.85 |   |
| Estimated payout percentage based on performance criteria  |   |       | 90      | %      |       |   | 70     | %          |   |   | 69 | % |
| Fair values of each nonvested performance share            |   | $          | 25.07   |   |       | $      | 19.50  |       |   | $ | 19.22 |   |

----

|                        |   | 2009   |    |   | 2008       |   |
|-----------------------------|--------|--------|---------|--------|------------|--------|
|                        |   |   |    |   | Weighted   |   |   |   |   |   | Weighted |   |
|                        |   |   |    |   | Average    |   |   |   |   |   | Average |   |
|                        |   | Shares |    |   | Fair Value |   |   | Shares |   |   | Fair Value |   |
| Nonvested shares at Jan. 1  |   |   | 156,807 |   |       | $      | 32.80 |   |   |   | 165,832 |   |   | $ | 30.66 |   |
| Granted                     |   |   | 51,236  |   |       |   | 29.40 |   |   |   | 47,922 |   |   |   | 35.60 |   |
| Vested                      |   |   | (79,459 | )      |       |   | 31.08 |   |   |   | (51,826 | ) |   |   | 28.27 |   |
| Forfeited                   |   |   | (3,235  | )      |       |   | 33.97 |   |   |   | (3,625 | ) |   |   | 35.69 |   |
| Nonvested shares at Sep. 30 |   |   | 125,349 |   |       |   | 32.47 |   |   |   | 158,303 |   |   |   | 32.82 |   |

|                         |   | 2009   |    |   | 2008       |   |
|------------------------------|--------|--------|---------|--------|------------|--------|
|                         |   |   |    |   | Weighted   |   |   |   |   |   | Weighted |   |
|                         |   |   |    |   | Average    |   |   |   |   |   | Average |   |
|                         |   | Shares |    |   | Fair Value |   |   | Shares |   |   | Fair Value |   |
| Nonvested shares at Jan. 1   |   |   | 124,185 |   |       | $      | 39.28 |   |   |   | 135,348 |   |   | $ | 32.42 |   |
| Granted during first quarter |   |   | 101,822 |   |       |   | 23.67 |   |   |   | 65,516 |   |   |   | 40.49 |   |
| Vested                       |   |   | --      |   |       |   | -- |   |   |   | (54,991 | ) |   |   | 28.20 |   |
| Forfeited                    |   |   | --      |   |       |   | -- |   |   |   | (21,688 | ) |   |   | 28.19 |   |
| Nonvested shares at Sep. 30  |   |   | 226,007 |   |       |   | 32.25 |   |   |   | 124,185 |   |   |   | 39.28 |   |

|                                   |   | 2009   |    |   | 2008     |   |
|----------------------------------------|--------|--------|---------|--------|----------|--------|
|                                   |   |   |    |   | Weighted |   |   |   |   |   | Weighted |   |
|                                   |   |   |    |   | Average  |   |   |   |   |   | Average |   |
|                                   |   |   |    |   | Exercise |   |   |   |   |   | Exercise |   |
|                                   |   | Shares |    |   | Price    |   |   | Shares |   |   | Price |   |
| Outstanding at Jan. 1                  |   |   | 497,183 |   |     | $      | 27.30 |   |   |   | 542,844 |   |   | $ | 27.45 |   |
| Exercised                              |   |   | (17,655 | )      |     |   | 22.27 |   |   |   | (45,661 | ) |   |   | 29.02 |   |
| Expired                                |   |   | (56,098 | )      |     |   | 29.88 |   |   |   | -- |   |   |   | -- |   |
| Forfeited                              |   |   | (16,877 | )      |     |   | 28.67 |   |   |   | -- |   |   |   | -- |   |
| Outstanding and exercisable at Sep. 30 |   |   | 406,553 |   |     |   | 27.11 |   |   |   | 497,183 |   |   |   | 27.30 |   |

|                                                  |   | Three Months |   |   | Nine Months |   |
|-------------------------------------------------------|--------|--------------|--------|--------|-------------|--------|
|                                                  |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| Cash received from stock options exercised            |   | $            | 0.3    |   |        | $      | -- |   |   | $ | 0.4 |   |   | $ | 1.3 |   |
| Aggregate intrinsic value of stock options exercised  |   |         | --     |   |        |   | -- |   |   |   | 0.1 |   |   |   | 0.3 |   |
| Income tax benefit from the exercise of stock options |   |         | --     |   |        |   | -- |   |   |   | -- |   |   |   | 0.1 |   |

----

| Shares outstanding at Jan. 1, 2009  |     110,449,099                                         |
|------------------------------------------|------------------------------------------------------------------------|
| Equity incentive plans (Note 6(b))       |            218,667        |
| Other (a)                                |             (33,490) |
| Shares outstanding at Sep. 30, 2009      |     110,634,276                                         |

| (a)   | Includes shares transferred from employees to Alliant Energy to satisfy tax withholding requirements in connection with the vesting of certain restricted stock under the EIP. |
|-----------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

----

|                                    |   | Three Months |   |   | Nine Months |   |
|-----------------------------------------|--------|--------------|--------|--------|-------------|--------|
|                                    |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| American Transmission Company LLC (ATC) |   | $            | (9.2   | )      |        | $      | (8.2 | ) |   | $ | (26.7 | ) |   | $ | (23.2 | ) |
| Other                                   |   |         | (0.3   | )      |        |   | (1.4 | ) |   |   | (0.6 | ) |   |   | (1.1 | ) |
|                                    |   | $            | (9.5   | )      |        | $      | (9.6 | ) |   | $ | (27.3 | ) |   | $ | (24.3 | ) |

|               |   | Three Months |   |   | Nine Months |   |
|--------------------|--------|--------------|--------|--------|-------------|--------|
|               |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| Operating revenues |   | $            | 132.3  |   |        | $      | 119.9 |   |   | $ | 387.5 |   |   | $ | 345.1 |   |
| Operating income   |   |         | 73.5   |   |        |   | 67.9 |   |   |   | 215.2 |   |   |   | 188.9 |   |
| Net income         |   |         | 53.8   |   |        |   | 49.7 |   |   |   | 157.4 |   |   |   | 137.8 |   |

|                          |   | Sep. 30, 2009 |   |   | Dec. 31, 2008     |   |
|-------------------------------|--------|---------------|--------|--------|-------------------|--------|
|                          |   | Carrying/Fair |   |   | Unrealized Gains, |   |   | Carrying/Fair |   |   | Unrealized Gains, |   |
|                          |   | Value         |   |   | Net of Tax        |   |   | Value |   |   | Net of Tax |   |
| Available-for-sale securities |   | $             | 4.3    |   |              | $      | 0.6 |   |   | $ | 3.8 |   |   | $ | 0.2 |   |

|                                                      |   | Alliant Energy |    |   | IPL    |   |    | WPL      |   |
|-----------------------------------------------------------|--------|----------------|---------|--------|--------|--------|---------|----------|--------|
|                                                      |   | Carrying       |    |   | Fair   |   |    | Carrying |   |   | Fair |   |   | Carrying |   |   | Fair |   |
|                                                      |   | Amount         |    |   | Value  |   |    | Amount   |   |   | Value |   |   | Amount |   |   | Value |   |
| Sep. 30, 2009                                             |   |           |    |   |   |   |    |     |   |   |   |   |   |   |   |   |   |   |
| Assets:                                                   |   |           |    |   |   |   |    |     |   |   |   |   |   |   |   |   |   |   |
| Derivative assets (Note 11(a))                            |   | $              | 33.0    |   |   | $      | 33.0    |     |   | $ | 18.3 |   |   | $ | 18.3 |   |   | $ | 14.6 |   |   | $ | 14.6 |   |
| Available-for-sale securities (Note 9(b))                 |   |           | 4.3     |   |   |   | 4.3     |     |   |   | 2.4 |   |   |   | 2.4 |   |   |   | -- |   |   |   | -- |   |
| Capitalization and liabilities:                           |   |           |    |   |   |   |    |     |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Long-term debt (including current maturities) (Note 8(b)) |   |           | 2,257.4 |   |   |   | 2,542.3 |     |   |   | 1,158.6 |   |   |   | 1,292.3 |   |   |   | 1,031.5 |   |   |   | 1,186.2 |   |
| Cumulative preferred stock of subsidiaries (Note 7(b))    |   |           | 243.8   |   |   |   | 259.8   |     |   |   | 183.8 |   |   |   | 209.4 |   |   |   | 60.0 |   |   |   | 50.4 |   |
| Derivative liabilities (Note 11(a))                       |   |           | 118.0   |   |   |   | 118.0   |     |   |   | 68.9 |   |   |   | 68.9 |   |   |   | 49.1 |   |   |   | 49.1 |   |
|                                                      |   |           |    |   |   |   |    |     |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Dec. 31, 2008                                             |   |           |    |   |   |   |    |     |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Assets:                                                   |   |           |    |   |   |   |    |     |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Derivative assets (Note 11(a))                            |   |           | 28.4    |   |   |   | 28.4    |     |   |   | 8.7 |   |   |   | 8.7 |   |   |   | 19.6 |   |   |   | 19.6 |   |
| Available-for-sale securities (Note 9(b))                 |   |           | 3.8     |   |   |   | 3.8     |     |   |   | 2.3 |   |   |   | 2.3 |   |   |   | -- |   |   |   | -- |   |
| Capitalization and liabilities:                           |   |           |    |   |   |   |    |     |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Long-term debt (including current maturities) (Note 8(b)) |   |           | 1,884.7 |   |   |   | 2,107.0 |     |   |   | 995.2 |   |   |   | 991.8 |   |   |   | 782.9 |   |   |   | 861.7 |   |
| Cumulative preferred stock of subsidiaries (Note 7(b))    |   |           | 243.8   |   |   |   | 242.1   |     |   |   | 183.8 |   |   |   | 192.3 |   |   |   | 60.0 |   |   |   | 49.8 |   |
| Derivative liabilities (Note 11(a))                       |   |           | 103.0   |   |   |   | 103.0   |     |   |   | 88.2 |   |   |   | 88.2 |   |   |   | 14.8 |   |   |   | 14.8 |   |

----

----

|                          |   | Fair Value   |   |   |    |   |   |        |   |   |        |   |
|-------------------------------|--------|--------------|--------|--------|---------|--------|--------|-------------|--------|--------|-------------|--------|
|                          |   | Measurements |   |   | Level 1 |   |   | Level 2 (a) |   |   | Level 3 (b) |   |
| Sep. 30, 2009                 |   |         |   |   |    |   |   |        |   |   |        |   |
| Assets:                       |   |         |   |   |    |   |   |        |   |   |        |   |
| Derivative assets             |   | $            | 33.0   |   |    | $      | 0.1    |        |   | $      | 18.2        |   |   | $ | 14.7 |   |
| Available-for-sale securities |   |         | 4.3    |   |    |   | 4.3    |        |   |   | --          |   |   |   | -- |   |
| Liabilities:                  |   |         |   |   |    |   |   |        |   |   |        |   |   |   |   |   |
| Derivative liabilities        |   |         | 118.0  |   |    |   | --     |        |   |   | 111.9       |   |   |   | 6.1 |   |
|                          |   |         |   |   |    |   |   |        |   |   |        |   |   |   |   |   |
| Dec. 31, 2008                 |   |         |   |   |    |   |   |        |   |   |        |   |   |   |   |   |
| Assets:                       |   |         |   |   |    |   |   |        |   |   |        |   |   |   |   |   |
| Derivative assets             |   |         | 28.4   |   |    |   | 0.1    |        |   |   | 2.6         |   |   |   | 25.7 |   |
| Available-for-sale securities |   |         | 3.8    |   |    |   | 3.8    |        |   |   | --          |   |   |   | -- |   |
| Liabilities:                  |   |         |   |   |    |   |   |        |   |   |        |   |   |   |   |   |
| Derivative liabilities        |   |         | 103.0  |   |    |   | --     |        |   |   | 92.0        |   |   |   | 11.0 |   |

| (a)   | Primarily electricity and natural gas swap contracts |
|-----------------|------------------------------------------------------|

| (b)   | Primarily embedded foreign currency derivatives and FTRs |
|-----------------|----------------------------------------------------------|

|                                                                                 |   | Derivative Assets and |   |
|--------------------------------------------------------------------------------------|--------|-----------------------|--------|
|                                                                                 |   | Liabilities, net      |   |
| Three months ended Sep. 30                                                           |   | 2009                  |   |   | 2008 |   |
| Beginning balance, July 1                                                            |   | $                     | 10.3   |   |   | $ | 26.3 |   |
| Total gains or (losses) (realized/unrealized) included in changes in net assets (a)  |   |                  | (4.5   | ) |   |   | 5.3 |   |
| Purchases, sales, issuances and settlements, net                                     |   |                  | (3.9   | ) |   |   | (9.2 | ) |
| Transfers in and/or out of Level 3                                                   |   |                  | 6.7    |   |   |   | -- |   |
| Ending balance, Sep. 30                                                              |   | $                     | 8.6    |   |   | $ | 22.4 |   |
|                                                                                 |   |                  |   |   |   |   |   |   |
| The amount of total gains or (losses) for the period included in changes in net      |   |                  |   |   |   |   |   |   |
| assets attributable to the change in unrealized gains or (losses) relating to assets |   |                  |   |   |   |   |   |   |
| and liabilities held at Sep. 30 (a)                                                  |   | $                     | (4.5   | ) |   | $ | 7.5 |   |
|                                                                                 |   |                  |   |   |   |   |   |   |
| Nine months ended Sep. 30                                                            |   |                  |   |   |   |   |   |   |
| Beginning balance, Jan. 1                                                            |   | $                     | 14.7   |   |   | $ | 27.7 |   |
| Total gains or (losses) (realized/unrealized) included in changes in net assets (a)  |   |                  | (5.0   | ) |   |   | 17.1 |   |
| Purchases, sales, issuances and settlements, net                                     |   |                  | (1.1   | ) |   |   | (22.4 | ) |
| Ending balance, Sep. 30                                                              |   | $                     | 8.6    |   |   | $ | 22.4 |   |
|                                                                                 |   |                  |   |   |   |   |   |   |
| The amount of total gains or (losses) for the period included in changes in net      |   |                  |   |   |   |   |   |   |
| assets attributable to the change in unrealized gains or (losses) relating to assets |   |                  |   |   |   |   |   |   |
| and liabilities held at Sep. 30 (a)                                                  |   | $                     | (4.5   | ) |   | $ | 22.4 |   |

| (a)   | Recorded in “Regulatory assets” and “Regulatory liabilities” on Alliant Energy’s Condensed Consolidated Balance Sheets. |
|-----------------|-------------------------------------------------------------------------------------------------------------------------------------------------------|

|                               |   | Fair Value at |   |   |    |   |   |    |   |   |    |   |   |       |   |
|------------------------------------|--------|---------------|--------|--------|---------|--------|--------|---------|--------|--------|---------|--------|--------|------------|--------|
|                               |   | Sep. 30, 2009 |   |   | Level 1 |   |   | Level 2 |   |   | Level 3 |   |   | Total Loss |   |
| IPL’s steam plant in service |   | $             | 4.6    |   |    | $      | --     |    |   | $      | --      |   |   | $          | 4.6    |   |   | $ | (4.0 | ) |

----

|                            | 2009   |   | 2010   |   | 2011   |   | 2012   |   | Total  |
|---------------------------------|--------|--------|--------|--------|--------|--------|--------|--------|--------|
| Alliant Energy                  |   |   |   |   |   |   |   |   |   |
| Commodity:                      |   |   |   |   |   |   |   |   |   |
| Electricity (MWhs)              | 880    |   | 4,107  |   | 1,435  |   | --     |   | 6,422  |
| FTRs (MWs)                      | 6      |   | 10     |   | --     |   | --     |   | 16     |
| Natural gas (Dths)              | 16,288 |   | 31,383 |   | 14,925 |   | 6,182  |   | 68,778 |
| Oil (gallons)                   | --     |   | 378    |   | --     |   | --     |   | 378    |
| Foreign exchange (Euro dollars) | --     |   | 44,420 |   | 14,806 |   | --     |   | 59,226 |
|                            |   |   |   |   |   |   |   |   |   |
| IPL                             |   |   |   |   |   |   |   |   |   |
| Commodity:                      |   |   |   |   |   |   |   |   |   |
| Electricity (MWhs)              | 256    |   | 2,281  |   | 221    |   | --     |   | 2,758  |
| FTRs (MWs)                      | 3      |   | 5      |   | --     |   | --     |   | 8      |
| Natural gas (Dths)              | 12,845 |   | 23,895 |   | 8,560  |   | --     |   | 45,300 |
| Foreign exchange (Euro dollars) | --     |   | 44,420 |   | 14,806 |   | --     |   | 59,226 |
|                            |   |   |   |   |   |   |   |   |   |
| WPL                             |   |   |   |   |   |   |   |   |   |
| Commodity:                      |   |   |   |   |   |   |   |   |   |
| Electricity (MWhs)              | 624    |   | 1,826  |   | 1,214  |   | --     |   | 3,664  |
| FTRs (MWs)                      | 3      |   | 5      |   | --     |   | --     |   | 8      |
| Natural gas (Dths)              | 3,443  |   | 7,488  |   | 6,365  |   | 6,182  |   | 23,478 |

----

|                               |   | Alliant Energy |   |   | IPL      |   |   | WPL      |   |
|------------------------------------|--------|----------------|--------|--------|----------|--------|--------|----------|--------|
|                               |   | Sep. 30,       |   |   | Dec. 31, |   |   | Sep. 30, |   |   | Dec. 31, |   |   | Sep. 30, |   |   | Dec. 31, |   |
|                               |   | 2009           |   |   | 2008     |   |   | 2009     |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |
| Current derivative assets          |   |           |   |   |     |   |   |     |   |   |   |   |   |   |   |   |   |   |
| Commodity contracts                |   | $              | 23.4   |   |     | $      | 18.1   |     |   | $ | 13.0 |   |   | $ | 7.4 |   |   | $ | 10.4 |   |   | $ | 10.7 |   |
| Foreign exchange contracts         |   |           | --     |   |     |   | --     |     |   |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |
|                               |   | $              | 23.4   |   |     | $      | 18.1   |     |   | $ | 13.0 |   |   | $ | 7.4 |   |   | $ | 10.4 |   |   | $ | 10.7 |   |
| Non-current derivative assets      |   |           |   |   |     |   |   |     |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Commodity contracts                |   | $              | 6.6    |   |     | $      | 2.4    |     |   | $ | 2.3 |   |   | $ | 1.3 |   |   | $ | 4.2 |   |   | $ | 1.0 |   |
| Foreign exchange contracts         |   |           | 3.0    |   |     |   | 7.9    |     |   |   | 3.0 |   |   |   | -- |   |   |   | -- |   |   |   | 7.9 |   |
|                               |   | $              | 9.6    |   |     | $      | 10.3   |     |   | $ | 5.3 |   |   | $ | 1.3 |   |   | $ | 4.2 |   |   | $ | 8.9 |   |
| Current derivative liabilities     |   |           |   |   |     |   |   |     |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Commodity contracts                |   | $              | 92.6   |   |     | $      | 76.7   |     |   | $ | 59.2 |   |   | $ | 68.9 |   |   | $ | 33.4 |   |   | $ | 7.8 |   |
| Foreign exchange contracts         |   |           | 1.5    |   |     |   | 1.9    |     |   |   | 0.1 |   |   |   | 1.1 |   |   |   | 1.4 |   |   |   | 0.8 |   |
|                               |   | $              | 94.1   |   |     | $      | 78.6   |     |   | $ | 59.3 |   |   | $ | 70.0 |   |   | $ | 34.8 |   |   | $ | 8.6 |   |
| Non-current derivative liabilities |   |           |   |   |     |   |   |     |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Commodity contracts                |   | $              | 23.7   |   |     | $      | 22.8   |     |   | $ | 9.6 |   |   | $ | 18.2 |   |   | $ | 14.1 |   |   | $ | 4.6 |   |
| Foreign exchange contracts         |   |           | 0.2    |   |     |   | 1.6    |     |   |   | -- |   |   |   | -- |   |   |   | 0.2 |   |   |   | 1.6 |   |
|                               |   | $              | 23.9   |   |     | $      | 24.4   |     |   | $ | 9.6 |   |   | $ | 18.2 |   |   | $ | 14.3 |   |   | $ | 6.2 |   |

|                             | Location of Gain (Loss) in Balance          |   | Gain (Loss)    |   |
|----------------------------------|---------------------------------------------|--------|----------------|--------|
|                             | Sheet or Statement of Income                |   | Alliant Energy |   |   | IPL |   |   | WPL |   |
| Three months ended Sep. 30, 2009 |                                        |   |           |   |   |   |   |   |   |   |
| Commodity contracts              | Regulatory assets (a)                       |   | $              | (11.3  | ) |   | $ | (6.9 | ) |   | $ | (4.4 | ) |
|                             | Regulatory liabilities (a)                  |   |           | 7.5    |   |   |   | 4.7 |   |   |   | 2.8 |   |
| Foreign exchange contracts       | Regulatory liabilities (a)                  |   |           | (4.5   | ) |   |   | (4.5 | ) |   |   | -- |   |
|                             |                                        |   |           |   |   |   |   |   |   |   |   |   |   |
| Nine months ended Sep. 30, 2009  |                                        |   |           |   |   |   |   |   |   |   |   |   |   |
| Commodity contracts              | Regulatory assets (a)                       |   |           | (105.1 | ) |   |   | (58.2 | ) |   |   | (46.9 | ) |
|                             | Regulatory liabilities (a)                  |   |           | 19.1   |   |   |   | 10.1 |   |   |   | 9.0 |   |
|                             | Non-regulated operation and maintenance (b) |   |           | 0.2    |   |   |   | -- |   |   |   | -- |   |
| Foreign exchange contracts       | Regulatory liabilities (a)                  |   |           | (4.9   | ) |   |   | (4.5 | ) |   |   | (0.4 | ) |

| (a)   | Balance Sheet |
|-----------------|---------------|

| (b)   | Statement of Income |
|-----------------|---------------------|

----

|           |   | Electric Utility Operating Revenues |   |   | Gas Utility Operating Revenues |   |
|----------------|--------|-------------------------------------|--------|--------|--------------------------------|--------|
|           |   | Three Months                        |   |   | Nine Months                    |   |   | Three Months |   |   | Nine Months |   |
|           |   | 2009                                |   |   | 2008                           |   |   | 2009 |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |
| IPL            |   | $                                   | --     |   |                           | $      | 4.6 |   |   | $ | (1.8 | ) |   | $ | 5.3 |   |   | $ | -- |   |   | $ | -- |   |   | $ | (1.4 | ) |   | $ | (1.5 | ) |
| WPL            |   |                                | --     |   |                           |   | 1.1 |   |   |   | (0.8 | ) |   |   | 1.1 |   |   |   | -- |   |   |   | -- |   |   |   | (1.2 | ) |   |   | (1.3 | ) |
| Alliant Energy |   | $                                   | --     |   |                           | $      | 5.7 |   |   | $ | (2.6 | ) |   | $ | 6.4 |   |   | $ | -- |   |   | $ | -- |   |   | $ | (2.6 | ) |   | $ | (2.8 | ) |

|              |   | Alliant Energy |   |   | IPL    |   |   | WPL    |   |
|-------------------|--------|----------------|--------|--------|--------|--------|--------|--------|--------|
| Wind projects (a) |   | $              | 396    |   |   | $      | 185    |   |   | $ | 211 |   |

----

| (a)   | Primarily related to capital purchase obligations under a master supply agreement executed in 2008 with Vestas for the purchase of 500 MW of wind turbine generator sets and related equipment to support IPL’s and WPL’s wind generation plans.  A portion of the future payments are denominated in Euros and therefore are subject to changewith fluctuations in currency exchange rates.  In addition, the master supply agreement includes pricing terms that are subject to change if steel prices change by more than 10% between measurement dates defined in the master supply agreement.  The amounts included in the above table reflect currency exchange rates and steel prices at Sep. 30, 2009. |
|-----------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|                                          |   | Alliant Energy |   |   | IPL    |   |   | WPL    |   |
|-----------------------------------------------|--------|----------------|--------|--------|--------|--------|--------|--------|--------|
| Purchased power (a):                          |   |           |   |   |   |   |   |   |   |
| DAEC (IPL)                                    |   | $              | 798    |   |   | $      | 798    |   |   | $ | -- |   |
| Kewaunee Nuclear Power Plant (Kewaunee) (WPL) |   |           | 317    |   |   |   | --     |   |   |   | 317 |   |
| Other                                         |   |           | 153    |   |   |   | 36     |   |   |   | 117 |   |
|                                          |   |           | 1,268  |   |   |   | 834    |   |   |   | 434 |   |
|                                          |   |           |   |   |   |   |   |   |   |   |   |   |
| Natural gas                                   |   |           | 428    |   |   |   | 177    |   |   |   | 251 |   |
| Coal (b)                                      |   |           | 383    |   |   |   | 107    |   |   |   | 40 |   |
| Emission allowances (c)                       |   |           | 45     |   |   |   | 45     |   |   |   | -- |   |
| Other (d)                                     |   |           | 48     |   |   |   | 29     |   |   |   | 6 |   |
|                                          |   | $              | 2,172  |   |   | $      | 1,192  |   |   | $ | 731 |   |

| (a)   | Includes payments required by purchased power agreements (PPAs) for capacity rights and minimum quantities of MWhs required to be purchased.  Excludes contracts that are considered operating leases. |
|-----------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| (b)   | Corporate Services has entered into system-wide coal purchase contracts on behalf of IPL and WPL that include minimum future commitments of $236 million that have not been directly assigned to IPL and WPL since the specific needs of each utility were not yet known as of Sep. 30, 2009. |
|-----------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| (c)   | IPL has entered into forward contracts to purchase sulfur dioxide (SO2) emission allowances with vintage years of 2014 through 2017 and nitrogen oxide (NOx) emission allowances with vintage years of 2009 through 2011 from various counterparties for $34 million and $11 million, respectively.  IPL may utilize any SO2 emission allowances acquiredunder these forward contracts to meet requirements under the Acid Rain Program regulations or the more stringent Clean Air Interstate Rule (CAIR) emission reduction standards.  IPL entered into the forward contracts to purchase NOx emission allowances solely for the purpose of compliance with the CAIR emission reduction standards.  IPL is currently monitoring the status of the forward contracts to purchase SO2 and NOx emission allowances in light of various court rulings in 2008 and anticipatedU.S. Environmental Protection Agency (EPA) proceedings regarding changes to CAIR.  Alliant Energy and IPL do not currently believe any losses from these forward contracts are probable and therefore have not recognized any loss contingency amounts related to the forward contracts as of Sep. 30, 2009.  Alliant Energy and IPL are currently unable to predict the ultimate impact these forward contracts will have on their financial condition and results of operations. |
|-----------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| (d)   | Includes individual commitments incurred during the normal course of business that exceeded $1 million at Sep. 30, 2009. |
|-----------------|--------------------------------------------------------------------------------------------------------------------------|

----

| Businesses/Assets Sold | Disposal Date                       |   | Maximum Limit |                             | Expiration Date |
|------------------------|-------------------------------------|--------|---------------|----------------------------------|-----------------|
| Brazil                 | First quarter of 2006               |   | $             | 10      |            | January 2011 |
| New Zealand            |    Fourth quarter of 2006 |   |          | 151 (a)                          |            | March 2012   |
| Mexico                 |    Second quarter of 2007 |   |          | 20           |            | June 2012     |

| (a)   | Based on exchange rates at Sep. 30, 2009 |
|-----------------|------------------------------------------|

----

----

|                                                 |   |             |   |   |                     |   |   |   |   |   | Alliant |   |
|------------------------------------------------------|--------|------------------|--------|--------|--------------------------|--------|--------|--------|--------|--------|---------|--------|
|                                                 |   | Utility Business |   |   | Non-regulated Businesses |   |   |   |   |   | Energy  |   |
|                                                 |   | Electric         |   |   | Gas                      |   |   | Other  |   |   | Total   |   |   | RMT |   |   | Other |   |   | Total |   |   | Other |   |   | Consolidated |   |
| Three Months Ended Sep. 30, 2009                     |   |             |   |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating revenues                                   |   | $                | 725.3  |   |                     | $      | 39.1   |   |   | $      | 20.1    |   |   | $ | 784.5 |   |   | $ | 89.9 |   |   | $ | 12.4 |   |   | $ | 102.3 |   |   | $ | (1.1 | ) |   | $ | 885.7 |   |
| Operating income (loss)                              |   |             | 161.5  |   |                     |   | (2.5   | )      |   |   | (0.9    | )      |   |   | 158.1 |   |   |   | (1.3 | ) |   |   | 4.8 |   |   |   | 3.5 |   |   |   | (1.7 | ) |   |   | 159.9 |   |
| Amounts attributable to Alliant Energy               |   |             |   |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| common shareowners:                                  |   |             |   |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Income (loss) from continuing operations, net of tax |   |             |   |   |                     |   |   |   |   |   |    |   |   |   | 89.2 |   |   |   | (0.7 | ) |   |   | 2.0 |   |   |   | 1.3 |   |   |   | (133.8 | ) |   |   | (43.3 | ) |
| Loss from discontinued operations, net of tax        |   |             |   |   |                     |   |   |   |   |   |    |   |   |   | -- |   |   |   | -- |   |   |   | (1.0 | ) |   |   | (1.0 | ) |   |   | -- |   |   |   | (1.0 | ) |
| Net income (loss) attributable to Alliant Energy     |   |             |   |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| common shareowners                                   |   |             |   |   |                     |   |   |   |   |   |    |   |   |   | 89.2 |   |   |   | (0.7 | ) |   |   | 1.0 |   |   |   | 0.3 |   |   |   | (133.8 | ) |   |   | (44.3 | ) |

----

|                                                 |   |             |    |   |                     |   |   |   |   |   | Alliant |   |
|------------------------------------------------------|--------|------------------|---------|--------|--------------------------|--------|--------|--------|--------|--------|---------|--------|
|                                                 |   | Utility Business |    |   | Non-regulated Businesses |   |   |   |   |   | Energy  |   |
|                                                 |   | Electric         |    |   | Gas                      |   |   | Other  |   |   | Total   |   |   | RMT |   |   | Other |   |   | Total |   |   | Other |   |   | Consolidated |   |
| Three Months Ended Sep. 30, 2008                     |   |             |    |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating revenues                                   |   | $                | 714.0   |   |                     | $      | 73.5   |   |   | $      | 30.8    |   |   | $ | 818.3 |   |   | $ | 144.4 |   |   | $ | 19.3 |   |   | $ | 163.7 |   |   | $ | (1.7 | ) |   | $ | 980.3 |   |
| Operating income (loss)                              |   |             | 174.6   |   |                     |   | (1.4   | )      |   |   | 1.1     |   |   |   | 174.3 |   |   |   | 11.7 |   |   |   | 4.2 |   |   |   | 15.9 |   |   |   | 0.3 |   |   |   | 190.5 |   |
| Amounts attributable to Alliant Energy               |   |             |    |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| common shareowners:                                  |   |             |    |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Income (loss) from continuing operations, net of tax |   |             |    |   |                     |   |   |   |   |   |    |   |   |   | 101.1 |   |   |   | 7.2 |   |   |   | (0.1 | ) |   |   | 7.1 |   |   |   | 0.9 |   |   |   | 109.1 |   |
| Loss from discontinued operations, net of tax        |   |             |    |   |                     |   |   |   |   |   |    |   |   |   | -- |   |   |   | -- |   |   |   | (0.6 | ) |   |   | (0.6 | ) |   |   | -- |   |   |   | (0.6 | ) |
| Net income (loss) attributable to Alliant Energy     |   |             |    |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| common shareowners                                   |   |             |    |   |                     |   |   |   |   |   |    |   |   |   | 101.1 |   |   |   | 7.2 |   |   |   | (0.7 | ) |   |   | 6.5 |   |   |   | 0.9 |   |   |   | 108.5 |   |
|                                                 |   |             |    |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Nine Months Ended Sep. 30, 2009                      |   |             |    |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating revenues                                   |   |             | 1,901.2 |   |                     |   | 361.8  |   |   |   | 69.4    |   |   |   | 2,332.4 |   |   |   | 212.4 |   |   |   | 37.1 |   |   |   | 249.5 |   |   |   | (4.0 | ) |   |   | 2,577.9 |   |
| Operating income (loss)                              |   |             | 267.7   |   |                     |   | 26.9   |   |   |   | (0.8    | )      |   |   | 293.8 |   |   |   | (6.6 | ) |   |   | 11.3 |   |   |   | 4.7 |   |   |   | (2.1 | ) |   |   | 296.4 |   |
| Amounts attributable to Alliant Energy               |   |             |    |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| common shareowners:                                  |   |             |    |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Income (loss) from continuing operations, net of tax |   |             |    |   |                     |   |   |   |   |   |    |   |   |   | 183.8 |   |   |   | (2.9 | ) |   |   | 4.4 |   |   |   | 1.5 |   |   |   | (126.9 | ) |   |   | 58.4 |   |
| Loss from discontinued operations, net of tax        |   |             |    |   |                     |   |   |   |   |   |    |   |   |   | -- |   |   |   | -- |   |   |   | (1.0 | ) |   |   | (1.0 | ) |   |   | -- |   |   |   | (1.0 | ) |
| Net income (loss) attributable to Alliant Energy     |   |             |    |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| common shareowners                                   |   |             |    |   |                     |   |   |   |   |   |    |   |   |   | 183.8 |   |   |   | (2.9 | ) |   |   | 3.4 |   |   |   | 0.5 |   |   |   | (126.9 | ) |   |   | 57.4 |   |
|                                                 |   |             |    |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Nine Months Ended Sep. 30, 2008                      |   |             |    |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating revenues                                   |   |             | 1,858.4 |   |                     |   | 503.1  |   |   |   | 64.3    |   |   |   | 2,425.8 |   |   |   | 325.1 |   |   |   | 53.2 |   |   |   | 378.3 |   |   |   | (4.4 | ) |   |   | 2,799.7 |   |
| Operating income                                     |   |             | 306.8   |   |                     |   | 45.3   |   |   |   | 3.1     |   |   |   | 355.2 |   |   |   | 21.8 |   |   |   | 18.2 |   |   |   | 40.0 |   |   |   | 2.4 |   |   |   | 397.6 |   |
| Amounts attributable to Alliant Energy               |   |             |    |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| common shareowners:                                  |   |             |    |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Income from continuing operations, net of tax        |   |             |    |   |                     |   |   |   |   |   |    |   |   |   | 192.9 |   |   |   | 13.7 |   |   |   | 14.4 |   |   |   | 28.1 |   |   |   | 8.0 |   |   |   | 229.0 |   |
| Income from discontinued operations, net of tax      |   |             |    |   |                     |   |   |   |   |   |    |   |   |   | -- |   |   |   | -- |   |   |   | 8.4 |   |   |   | 8.4 |   |   |   | -- |   |   |   | 8.4 |   |
| Net income attributable to Alliant Energy            |   |             |    |   |                     |   |   |   |   |   |    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| common shareowners                                   |   |             |    |   |                     |   |   |   |   |   |    |   |   |   | 192.9 |   |   |   | 13.7 |   |   |   | 22.8 |   |   |   | 36.5 |   |   |   | 8.0 |   |   |   | 237.4 |   |

|                          |   | Alliant Energy |   |   | IPL      |   |   | WPL      |   |
|-------------------------------|--------|----------------|--------|--------|----------|--------|--------|----------|--------|
|                          |   | Sep. 30,       |   |   | Dec. 31, |   |   | Sep. 30, |   |   | Dec. 31, |   |   | Sep. 30, |   |   | Dec. 31, |   |
|                          |   | 2009           |   |   | 2008     |   |   | 2009     |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |
| Purchased emission allowances |   | $              | 66.1   |   |     | $      | 65.1   |     |   | $ | 58.6 |   |   | $ | 57.9 |   |   | $ | 7.5 |   |   | $ | 7.2 |   |
| Accumulated amortization      |   |           | 12.4   |   |     |   | 0.8    |     |   |   | 9.2 |   |   |   | 0.8 |   |   |   | 3.2 |   |   |   | -- |   |

|           |   | Three Months |   |   | Nine Months |   |
|----------------|--------|--------------|--------|--------|-------------|--------|
|           |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| IPL            |   | $            | 3.0    |   |        | $      | -- |   |   | $ | 8.4 |   |   | $ | -- |   |
| WPL            |   |         | 1.1    |   |        |   | -- |   |   |   | 3.2 |   |   |   | -- |   |
| Alliant Energy |   | $            | 4.1    |   |        | $      | -- |   |   | $ | 11.6 |   |   | $ | -- |   |

----

|           |   | 2009   |   |   | 2010   |   |   | 2011   |   |   | 2012 |   |   | 2013   |   |
|----------------|--------|--------|--------|--------|--------|--------|--------|--------|--------|--------|------|--------|--------|--------|--------|
| IPL            |   | $      | 11.5   |   |   | $      | 12.2   |   |   | $      | 13.4 |   |   | $      | 9.3    |   |   | $ | 8.1 |   |
| WPL            |   |   | 4.1    |   |   |   | 3.2    |   |   |   | 0.2  |   |   |   | --     |   |   |   | -- |   |
| Alliant Energy |   | $      | 15.6   |   |   | $      | 15.4   |   |   | $      | 13.6 |   |   | $      | 9.3    |   |   | $ | 8.1 |   |

|                                                   |   | Three Months |   |   | Nine Months |   |
|--------------------------------------------------------|--------|--------------|--------|--------|-------------|--------|
|                                                   |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| Operating expenses                                     |   | $            | --     |   |        | $      | -- |   |   | $ | -- |   |   | $ | 0.2 |   |
| Income tax expense (benefit) (a)                       |   |         | 1.0    |   |        |   | 0.6 |   |   |   | 1.0 |   |   |   | (8.6 | ) |
| Income (loss) from discontinued operations, net of tax |   | $            | (1.0   | )      |        | $      | (0.6 | ) |   | $ | (1.0 | ) |   | $ | 8.4 |   |

| (a)   | In the second quarter of 2008, Alliant Energy reached a settlement with the IRS related to the audit of its U.S. federal income tax returns for calendar years 2002 through 2004.  As a result of completing the audit and recording known adjustments for the tax returns for calendar years 2005 and 2006, Alliant Energy recorded decreases in its liabilitiesfor unrecognized tax benefits and related interest, net of tax, and changes to its provision for income taxes including the impact of $9 million of income tax benefits allocated to its discontinued operations in the second quarter of 2008 largely related to its former Australia and China businesses. |
|-----------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|                                  |   | Alliant Energy |   |   | IPL    |   |   | WPL    |   |
|---------------------------------------|--------|----------------|--------|--------|--------|--------|--------|--------|--------|
|                                  |   | 2009           |   |   | 2008   |   |   | 2009   |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |
| Balance at Jan. 1                     |   | $              | 48.4   |   |   | $      | 42.8   |   |   | $ | 30.5 |   |   | $ | 30.9 |   |   | $ | 17.9 |   |   | $ | 11.9 |   |
| Liabilities incurred (a) (b)          |   |           | 11.9   |   |   |   | 7.1    |   |   |   | 11.9 |   |   |   | 2.5 |   |   |   | -- |   |   |   | 4.6 |   |
| Accretion expense                     |   |           | 2.2    |   |   |   | 1.8    |   |   |   | 1.3 |   |   |   | 1.2 |   |   |   | 0.9 |   |   |   | 0.6 |   |
| Revisions in estimated cash flows (a) |   |           | --     |   |   |   | 6.1    |   |   |   | -- |   |   |   | 6.1 |   |   |   | -- |   |   |   | -- |   |
| Liabilities settled (a)               |   |           | (1.9   | )      |   |   | (8.9   | )      |   |   | (1.8 | ) |   |   | (8.6 | ) |   |   | (0.1 | ) |   |   | (0.3 | ) |
| Balance at Sep. 30                    |   | $              | 60.6   |   |   | $      | 48.9   |   |   | $ | 41.9 |   |   | $ | 32.1 |   |   | $ | 18.7 |   |   | $ | 16.8 |   |

| (a)   | In 2009, IPL recorded liabilities settled of $1.2 million due to expenditures for asbestos and lead remediation at its Sixth Street and Prairie Creek Generating Stations required as a result of the impacts of the severe Midwest flooding at these generating stations in June 2008.  In 2008, IPL recorded changes to liabilities incurred, revisionsin estimated cash flows and liabilities settled due to asbestos remediation at its Sixth Street and Prairie Creek Generating Stations as a result of the impacts of the severe Midwest flooding at these generating stations in June 2008. |
|-----------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| (b)   | In 2009, IPL recorded AROs of $11.9 million related to its Whispering Willow - East wind project.  In 2008, WPL recorded AROs of $4.6 million related to its Cedar Ridge wind project. |
|-----------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

|                |   | Three Months |   |   | Nine Months |   |
|---------------------|--------|--------------|--------|--------|-------------|--------|
|                |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| ATC billings to WPL |   | $            | 20.8   |   |        | $      | 20.7 |   |   | $ | 63.0 |   |   | $ | 61.6 |   |
| WPL billings to ATC |   |         | 4.0    |   |        |   | 1.7 |   |   |   | 8.8 |   |   |   | 6.6 |   |

|                                        | Three Months |   | Nine Months |
|---------------------------------------------|--------------|--------|-------------|
|                                        | 2009         |   | 2008        |   | 2009 |   | 2008 |
| Weighted average common shares outstanding: |         |   |        |   |   |   |   |
| Basic EPS calculation                       | 110,288      |   | 110,182     |   | 110,257 |   | 110,166 |
| Effect of dilutive share-based awards       | --           |   | 131         |   | 83 |   | 147 |
| Diluted EPS calculation                     | 110,288      |   | 110,313     |   | 110,340 |   | 110,313 |

|                                                |   | Three Months |    |   | Nine Months |   |
|-----------------------------------------------------|--------|--------------|---------|--------|-------------|--------|
|                                                |   | 2009         |    |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| Options to purchase shares of common stock          |   |         | 308,458 |   |        |   | -- |   |   |   | 363,206 |   |   |   | -- |   |
| Weighted average exercise price of options excluded |   | $            | 29.31   |   |        | $      | -- |   |   | $ | 29.06 |   |   | $ | -- |   |

|           |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |       |   |   |   |   |   | Less: amount |   |   | Present value of net |   |
|----------------|--------|--------|--------|--------|--------|--------|--------|--------|--------|--------|--------|--------|--------|--------|--------|--------|------------|--------|--------|--------|--------|--------|--------------|--------|--------|----------------------|--------|
|           |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |       |   |   |   |   |   | representing |   |   | minimum capital      |   |
|           |   | 2009   |   |   | 2010   |   |   | 2011   |   |   | 2012   |   |   | 2013   |   |   | Thereafter |   |   | Total  |   |   | interest     |   |   | lease payments       |   |
| Capital leases |   | $      | --     |   |   | $      | 2      |   |   | $      | 1      |   |   | $      | 1      |   |       | $      | 1      |   |   | $      | 3            |   |   | $                    | 8      |   |   | $ | 2 |   |   | $ | 6 |   |

----

| INTERSTATE POWER AND LIGHT COMPANY                                                                                    |   |
|-----------------------------------------------------------------------------------------------------------------------|--------|
| CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)                                                               |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                  |   | For the Three Months |   |   | For the Nine Months |   |
|                                                                                                                  |   | Ended September 30, |   |   | Ended September 30, |   |
|                                                                                                                  |   | 2009 |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |
|                                                                                                                  |   | (in millions) |   |
| Operating revenues:                                                                                                   |   |   |   |   |   |   |   |   |   |   |   |   |
|   Electric utility                                                                                          |   | $ | 417.9 |   |   | $ | 394.8 |   |   | $ | 1,022.7 |   |   | $ | 973.6 |   |
|   Gas utility                                                                                               |   |   | 22.6 |   |   |   | 42.2 |   |   |   | 208.1 |   |   |   | 292.9 |   |
|   Steam and other                                                                                           |   |   | 17.4 |   |   |   | 27.4 |   |   |   | 63.3 |   |   |   | 56.6 |   |
|                                                                                                                  |   |   | 457.9 |   |   |   | 464.4 |   |   |   | 1,294.1 |   |   |   | 1,323.1 |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating expenses:                                                                                                   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|   Electric production fuel and purchased power                                                              |   |   | 169.6 |   |   |   | 160.4 |   |   |   | 455.6 |   |   |   | 423.4 |   |
|   Electric transmission service                                                                             |   |   | 31.4 |   |   |   | 25.4 |   |   |   | 101.3 |   |   |   | 67.9 |   |
|   Cost of gas sold                                                                                          |   |   | 9.0 |   |   |   | 28.2 |   |   |   | 141.2 |   |   |   | 220.1 |   |
|   Other operation and maintenance                                                                           |   |   | 80.2 |   |   |   | 99.6 |   |   |   | 271.6 |   |   |   | 277.7 |   |
|   Depreciation and amortization                                                                             |   |   | 38.5 |   |   |   | 32.2 |   |   |   | 110.9 |   |   |   | 97.3 |   |
|   Taxes other than income taxes                                                                             |   |   | 12.6 |   |   |   | 13.9 |   |   |   | 39.0 |   |   |   | 41.8 |   |
|                                                                                                                  |   |   | 341.3 |   |   |   | 359.7 |   |   |   | 1,119.6 |   |   |   | 1,128.2 |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating income                                                                                                      |   |   | 116.6 |   |   |   | 104.7 |   |   |   | 174.5 |   |   |   | 194.9 |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Interest expense and other:                                                                                           |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|   Interest expense                                                                                          |   |   | 20.6 |   |   |   | 14.8 |   |   |   | 56.4 |   |   |   | 44.2 |   |
|   Allowance for funds used during construction                                                              |   |   | (12.6 | ) |   |   | (5.2 | ) |   |   | (31.8 | ) |   |   | (8.4 | ) |
|   Interest income                                                                                           |   |   | (0.3 | ) |   |   | (0.1 | ) |   |   | (0.7 | ) |   |   | (0.6 | ) |
|                                                                                                                  |   |   | 7.7 |   |   |   | 9.5 |   |   |   | 23.9 |   |   |   | 35.2 |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Income before income taxes                                                                                            |   |   | 108.9 |   |   |   | 95.2 |   |   |   | 150.6 |   |   |   | 159.7 |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Income taxes                                                                                                          |   |   | 36.1 |   |   |   | 32.1 |   |   |   | 16.7 |   |   |   | 46.9 |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Net income                                                                                                            |   |   | 72.8 |   |   |   | 63.1 |   |   |   | 133.9 |   |   |   | 112.8 |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Preferred dividend requirements                                                                                       |   |   | 3.8 |   |   |   | 3.8 |   |   |   | 11.5 |   |   |   | 11.5 |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Earnings available for common stock                                                                                   |   | $ | 69.0 |   |   | $ | 59.3 |   |   | $ | 122.4 |   |   | $ | 101.3 |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                                  |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these statements.  |   |

----

| INTERSTATE POWER AND LIGHT COMPANY                                                                              |   |
|-----------------------------------------------------------------------------------------------------------------|--------|
| CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)                                                               |   |
|                                                                                                            |   |   |   |   |   |   |
|                                                                                                            |   | September 30, |   |   | December 31, |   |
| ASSETS                                                                                                          |   | 2009 |   |   | 2008 |   |
|                                                                                                            |   | (in millions) |   |
| Property, plant and equipment:                                                                                  |   |   |   |   |   |   |
|   Electric plant in service                                                                           |   | $ | 3,823.7 |   |   | $ | 3,518.5 |   |
|   Gas plant in service                                                                                |   |   | 401.0 |   |   |   | 391.5 |   |
|   Steam plant in service                                                                              |   |   | 50.4 |   |   |   | 54.2 |   |
|   Other plant in service                                                                              |   |   | 253.8 |   |   |   | 228.7 |   |
|   Accumulated depreciation                                                                            |   |   | (1,708.1 | ) |   |   | (1,600.3 | ) |
|     Net plant                                                                               |   |   | 2,820.8 |   |   |   | 2,592.6 |   |
|   Construction work in progress:                                                                      |   |   |   |   |   |   |   |   |
|     Whispering Willow - East wind project                                                   |   |   | 432.0 |   |   |   | 189.4 |   |
|     Other                                                                                   |   |   | 163.9 |   |   |   | 205.8 |   |
|   Other, less accumulated depreciation                                                                |   |   | 24.1 |   |   |   | 18.6 |   |
|                                                                                                            |   |   | 3,440.8 |   |   |   | 3,006.4 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Current assets:                                                                                                 |   |   |   |   |   |   |   |   |
|   Cash and cash equivalents                                                                           |   |   | 5.1 |   |   |   | 6.2 |   |
|   Accounts receivable:                                                                                |   |   |   |   |   |   |   |   |
|     Customer, less allowance for doubtful accounts                                          |   |   | 57.1 |   |   |   | 107.1 |   |
|     Unbilled utility revenues                                                               |   |   | 70.4 |   |   |   | 93.7 |   |
|     Other, less allowance for doubtful accounts                                             |   |   | 19.9 |   |   |   | 60.0 |   |
|   Income tax refunds receivable                                                                       |   |   | 101.4 |   |   |   | 48.6 |   |
|   Production fuel, at weighted average cost                                                           |   |   | 100.0 |   |   |   | 70.0 |   |
|   Materials and supplies, at weighted average cost                                                    |   |   | 30.0 |   |   |   | 30.4 |   |
|   Gas stored underground, at weighted average cost                                                    |   |   | 20.5 |   |   |   | 27.1 |   |
|   Regulatory assets                                                                                   |   |   | 67.8 |   |   |   | 79.8 |   |
|   Derivative assets                                                                                   |   |   | 13.0 |   |   |   | 7.4 |   |
|   Other                                                                                               |   |   | 16.2 |   |   |   | 30.7 |   |
|                                                                                                            |   |   | 501.4 |   |   |   | 561.0 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Investments                                                                                                     |   |   | 14.8 |   |   |   | 15.2 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Other assets:                                                                                                   |   |   |   |   |   |   |   |   |
|   Regulatory assets                                                                                   |   |   | 662.9 |   |   |   | 554.5 |   |
|   Deferred charges and other                                                                          |   |   | 73.5 |   |   |   | 73.8 |   |
|                                                                                                            |   |   | 736.4 |   |   |   | 628.3 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Total assets                                                                                                    |   | $ | 4,693.4 |   |   | $ | 4,210.9 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these statements. |   |

----

|  INTERSTATE POWER AND LIGHT COMPANY                                                                        |   |
|-----------------------------------------------------------------------------------------------------------------|--------|
| CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Continued)                                                   |   |
|                                                                                                            |   |   |   |   |   |   |
|                                                                                                            |   | September 30, |   |   | December 31, |   |
| CAPITALIZATION AND LIABILITIES                                                                                  |   | 2009 |   |   | 2008 |   |
|                                                                                                            |   | (in millions, except per |   |
|                                                                                                            |   | share and share amounts) |   |
| Capitalization:                                                                                                 |   |   |   |   |   |   |
|   Interstate Power and Light Company common equity:                                                   |   |   |   |   |   |   |
|      Common stock - $2.50 par value - authorized 24,000,000 shares;                         |   |   |   |   |
|        13,370,788 shares outstanding                                         |   | $ | 33.4 |   |   | $ | 33.4 |   |
|      Additional paid-in capital                                                        |   |   | 1,069.1 |   |   |   | 998.1 |   |
|      Retained earnings                                                                 |   |   | 239.2 |   |   |   | 116.8 |   |
|        Total Interstate Power and Light Company common equity                |   |   | 1,341.7 |   |   |   | 1,148.3 |   |
|   Cumulative preferred stock                                                                          |   |   | 183.8 |   |   |   | 183.8 |   |
|        Total equity                                                          |   |   | 1,525.5 |   |   |   | 1,332.1 |   |
|   Long-term debt, net (excluding current portion)                                                     |   |   | 1,158.6 |   |   |   | 860.2 |   |
|                                                                                                            |   |   | 2,684.1 |   |   |   | 2,192.3 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Current liabilities:                                                                                            |   |   |   |   |   |   |   |   |
|   Current maturities of long-term debt                                                                |   |   | - |   |   |   | 135.0 |   |
|   Commercial paper                                                                                    |   |   | - |   |   |   | 42.4 |   |
|   Accounts payable                                                                                    |   |   | 152.5 |   |   |   | 222.4 |   |
|   Accounts payable to associated companies                                                            |   |   | 40.3 |   |   |   | 30.5 |   |
|   Regulatory liabilities                                                                              |   |   | 83.9 |   |   |   | 51.0 |   |
|   Accrued interest                                                                                    |   |   | 21.8 |   |   |   | 18.9 |   |
|   Accrued taxes                                                                                       |   |   | 34.6 |   |   |   | 46.4 |   |
|   Derivative liabilities                                                                              |   |   | 59.3 |   |   |   | 70.0 |   |
|   Other                                                                                               |   |   | 36.7 |   |   |   | 51.6 |   |
|                                                                                                            |   |   | 429.1 |   |   |   | 668.2 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Other long-term liabilities and deferred credits:                                                               |   |   |   |   |   |   |   |   |
|   Deferred income taxes                                                                               |   |   | 644.1 |   |   |   | 500.0 |   |
|   Regulatory liabilities                                                                              |   |   | 539.0 |   |   |   | 463.8 |   |
|   Pension and other benefit obligations                                                               |   |   | 194.3 |   |   |   | 213.9 |   |
|   Other                                                                                               |   |   | 202.8 |   |   |   | 172.7 |   |
|                                                                                                            |   |   | 1,580.2 |   |   |   | 1,350.4 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Total capitalization and liabilities                                                                            |   | $ | 4,693.4 |   |   | $ | 4,210.9 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these statements. |   |

----

| INTERSTATE POWER AND LIGHT COMPANY                                                                              |   |
|-----------------------------------------------------------------------------------------------------------------|--------|
| CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)                                                     |   |
|                                                                                                            |   |   |   |   |   |   |
|                                                                                                            |   | For the Nine Months Ended September 30, |   |
|                                                                                                            |   | 2009 |   |   | 2008 |   |
|                                                                                                            |   | (in millions) |   |
| Cash flows from operating activities:                                                                           |   |   |   |   |   |   |
|   Net income                                                                                          |   | $ | 133.9 |   |   | $ | 112.8 |   |
|   Adjustments to reconcile net income to net cash flows from operating activities:                    |   |
|      Depreciation and amortization                                                     |   |   | 110.9 |   |   |   | 97.3 |   |
|      Deferred tax expense (benefit) and investment tax credits                         |   |   | 54.0 |   |   |   | (22.8 | ) |
|      Equity component of allowance for funds used during construction                  |   |   | (24.9 | ) |   |   | (5.8 | ) |
|      Other                                                                             |   |   | 11.5 |   |   |   | 13.1 |   |
|   Other changes in assets and liabilities:                                                            |   |   |   |   |   |   |   |   |
|      Accounts receivable                                                               |   |   | 77.7 |   |   |   | (40.8 | ) |
|      Sale of accounts receivable                                                       |   |   | 35.0 |   |   |   | 50.0 |   |
|      Income tax refunds receivable                                                     |   |   | (52.8 | ) |   |   | 29.1 |   |
|      Production fuel                                                                   |   |   | (30.0 | ) |   |   | (13.0 | ) |
|      Regulatory assets                                                                 |   |   | (105.1 | ) |   |   | (33.4 | ) |
|      Prepaid gas costs                                                                 |   |   | 22.7 |   |   |   | (18.4 | ) |
|      Accounts payable                                                                  |   |   | (50.8 | ) |   |   | 6.9 |   |
|      Accounts payable to associated companies                                          |   |   | 9.8 |   |   |   | (21.8 | ) |
|      Regulatory liabilities                                                            |   |   | 110.3 |   |   |   | (18.5 | ) |
|      Derivative liabilities                                                            |   |   | (19.3 | ) |   |   | 28.5 |   |
|      Deferred income taxes                                                             |   |   | 88.7 |   |   |   | 17.9 |   |
|      Non-current taxes payable                                                         |   |   | 34.7 |   |   |   | 1.8 |   |
|      Pension and other benefit obligations                                             |   |   | (19.6 | ) |   |   | (0.6 | ) |
|      Other                                                                             |   |   | (36.7 | ) |   |   | (23.1 | ) |
|        Net cash flows from operating activities                              |   |   | 350.0 |   |   |   | 159.2 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Cash flows used for investing activities:                                                                       |   |   |   |   |   |   |   |   |
|      Utility construction and acquisition expenditures                                 |   |   | (576.2 | ) |   |   | (356.4 | ) |
|      Advances for customer energy efficiency projects                                  |   |   | (0.7 | ) |   |   | (1.0 | ) |
|      Collections of advances for customer energy efficiency projects                   |   |   | 3.9 |   |   |   | 3.8 |   |
|      Insurance proceeds received for property damages                                  |   |   | 37.7 |   |   |   | 3.7 |   |
|      Other                                                                             |   |   | (12.2 | ) |   |   | 0.9 |   |
|        Net cash flows used for investing activities                          |   |   | (547.5 | ) |   |   | (349.0 | ) |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Cash flows from financing activities:                                                                           |   |   |   |   |   |   |   |   |
|      Common stock dividends                                                            |   |   | - |   |   |   | (29.1 | ) |
|      Preferred stock dividends                                                         |   |   | (11.5 | ) |   |   | (11.5 | ) |
|      Capital contribution from parent                                                  |   |   | 150.0 |   |   |   | 200.0 |   |
|      Repayment of capital to parent                                                    |   |   | (79.0 | ) |   |   | - |   |
|      Proceeds from issuance of long-term debt                                          |   |   | 300.0 |   |   |   | - |   |
|      Reductions in long-term debt                                                      |   |   | (135.0 | ) |   |   | (1.0 | ) |
|      Net change in short-term borrowings                                               |   |   | (42.4 | ) |   |   | (20.7 | ) |
|      Changes in cash overdrafts                                                        |   |   | 19.1 |   |   |   | 13.9 |   |
|      Other                                                                             |   |   | (4.8 | ) |   |   | (0.5 | ) |
|        Net cash flows from financing activities                              |   |   | 196.4 |   |   |   | 151.1 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Net decrease in cash and cash equivalents                                                                       |   |   | (1.1 | ) |   |   | (38.7 | ) |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Cash and cash equivalents at beginning of period                                                                |   |   | 6.2 |   |   |   | 39.4 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Cash and cash equivalents at end of period                                                                      |   | $ | 5.1 |   |   | $ | 0.7 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Supplemental cash flows information:                                                                            |   |   |   |   |   |   |   |   |
|   Cash paid (refunded) during the period for:                                                         |   |   |   |   |   |   |   |   |
|      Interest                                                                          |   | $ | 53.3 |   |   | $ | 45.4 |   |
|      Income taxes, net of refunds                                                      |   | $ | (54.8 | ) |   | $ | 34.4 |   |
|   Noncash investing and financing activities:                                                         |   |   |   |   |   |   |   |   |
|      Capital lease obligations incurred                                                |   | $ | 1.1 |   |   | $ | - |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these statements. |   |

----

|                           |   | Qualified Pension Benefits |   |   | Other Postretirement Benefits |   |
|--------------------------------|--------|----------------------------|--------|--------|-------------------------------|--------|
|                           |   | Three Months               |   |   | Nine Months                   |   |   | Three Months |   |   | Nine Months |   |
|                           |   | 2009                       |   |   | 2008                          |   |   | 2009 |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |
| Service cost                   |   | $                          | 1.5    |   |                          | $      | 1.5 |   |   | $ | 4.5 |   |   | $ | 4.5 |   |   | $ | 0.7 |   |   | $ | 0.7 |   |   | $ | 2.3 |   |   | $ | 2.1 |   |
| Interest cost                  |   |                       | 4.0    |   |                          |   | 3.9 |   |   |   | 12.1 |   |   |   | 11.8 |   |   |   | 1.9 |   |   |   | 1.9 |   |   |   | 5.5 |   |   |   | 5.5 |   |
| Expected return on plan assets |   |                       | (3.5   | )      |                          |   | (5.3 | ) |   |   | (10.5 | ) |   |   | (16.1 | ) |   |   | (1.0 | ) |   |   | (1.6 | ) |   |   | (3.1 | ) |   |   | (4.6 | ) |
| Amortization of:               |   |                       |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Transition obligation          |   |                       | --     |   |                          |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | 0.1 |   |   |   | 0.1 |   |
| Prior service cost (credit)    |   |                       | 0.2    |   |                          |   | 0.2 |   |   |   | 0.6 |   |   |   | 0.7 |   |   |   | (0.4 | ) |   |   | (0.4 | ) |   |   | (1.2 | ) |   |   | (1.2 | ) |
| Actuarial loss                 |   |                       | 2.4    |   |                          |   | 0.1 |   |   |   | 7.0 |   |   |   | 0.2 |   |   |   | 1.0 |   |   |   | 0.5 |   |   |   | 3.0 |   |   |   | 1.5 |   |
|                           |   | $                          | 4.6    |   |                          | $      | 0.4 |   |   | $ | 13.7 |   |   | $ | 1.1 |   |   | $ | 2.2 |   |   | $ | 1.1 |   |   | $ | 6.6 |   |   | $ | 3.4 |   |

----

|                              |   | Pension Benefits |   |   | Other Postretirement Benefits |   |
|-----------------------------------|--------|------------------|--------|--------|-------------------------------|--------|
|                              |   | Three Months     |   |   | Nine Months                   |   |   | Three Months |   |   | Nine Months |   |
|                              |   | 2009             |   |   | 2008                          |   |   | 2009 |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |
| Non-bargaining IPL employees      |   |             |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| participating in other plans      |   | $                | 1.0    |   |                          | $      | (0.9 | ) |   | $ | 3.0 |   |   | $ | (2.7 | ) |   |   | N/A |   |   |   | N/A |   |   |   | N/A |   |   |   | N/A |   |
| Allocated Corporate Service costs |   |             | 0.4    |   |                          |   | 0.3 |   |   |   | 1.3 |   |   |   | 0.8 |   |   | $ | 0.4 |   |   | $ | 0.4 |   |   | $ | 1.3 |   |   | $ | 1.1 |   |

|                          |   | Fair Value   |   |   |    |   |   |    |   |   |    |   |
|-------------------------------|--------|--------------|--------|--------|---------|--------|--------|---------|--------|--------|---------|--------|
|                          |   | Measurements |   |   | Level 1 |   |   | Level 2 |   |   | Level 3 |   |
| Sep. 30, 2009                 |   |         |   |   |    |   |   |    |   |   |    |   |
| Assets:                       |   |         |   |   |    |   |   |    |   |   |    |   |
| Derivative assets             |   | $            | 18.3   |   |    | $      | --     |    |   | $      | 9.3     |   |   | $ | 9.0 |   |
| Available-for-sale securities |   |         | 2.4    |   |    |   | 2.4    |    |   |   | --      |   |   |   | -- |   |
| Liabilities:                  |   |         |   |   |    |   |   |    |   |   |    |   |   |   |   |   |
| Derivative liabilities        |   |         | 68.9   |   |    |   | --     |    |   |   | 66.1    |   |   |   | 2.8 |   |
|                          |   |         |   |   |    |   |   |    |   |   |    |   |   |   |   |   |
| Dec. 31, 2008                 |   |         |   |   |    |   |   |    |   |   |    |   |   |   |   |   |
| Assets:                       |   |         |   |   |    |   |   |    |   |   |    |   |   |   |   |   |
| Derivative assets             |   |         | 8.7    |   |    |   | --     |    |   |   | 1.6     |   |   |   | 7.1 |   |
| Available-for-sale securities |   |         | 2.3    |   |    |   | 2.3    |    |   |   | --      |   |   |   | -- |   |
| Liabilities:                  |   |         |   |   |    |   |   |    |   |   |    |   |   |   |   |   |
| Derivative liabilities        |   |         | 88.2   |   |    |   | --     |    |   |   | 81.4    |   |   |   | 6.8 |   |

|                                                                                 |   | Derivative Assets and |   |
|--------------------------------------------------------------------------------------|--------|-----------------------|--------|
|                                                                                 |   | Liabilities, net      |   |
| Three months ended Sep. 30                                                           |   | 2009                  |   |   | 2008 |   |
| Beginning balance, July 1                                                            |   | $                     | 13.8   |   |   | $ | 7.9 |   |
| Total gains or (losses) (realized/unrealized) included in changes in net assets (a)  |   |                  | (4.5   | ) |   |   | (2.6 | ) |
| Purchases, sales, issuances and settlements, net                                     |   |                  | (2.8   | ) |   |   | (3.0 | ) |
| Transfers in and/or out of Level 3                                                   |   |                  | (0.3   | ) |   |   | -- |   |
| Ending balance, Sep. 30                                                              |   | $                     | 6.2    |   |   | $ | 2.3 |   |
|                                                                                 |   |                  |   |   |   |   |   |   |
| The amount of total gains or (losses) for the period included in changes in net      |   |                  |   |   |   |   |   |   |
| assets attributable to the change in unrealized gains or (losses) relating to assets |   |                  |   |   |   |   |   |   |
| and liabilities held at Sep. 30 (a)                                                  |   | $                     | (4.5   | ) |   | $ | -- |   |
|                                                                                 |   |                  |   |   |   |   |   |   |
| Nine months ended Sep. 30                                                            |   |                  |   |   |   |   |   |   |
| Beginning balance, Jan. 1                                                            |   | $                     | 0.3    |   |   | $ | 15.0 |   |
| Total gains or (losses) (realized/unrealized) included in changes in net assets (a)  |   |                  | (4.5   | ) |   |   | (2.2 | ) |
| Purchases, sales, issuances and settlements, net                                     |   |                  | 10.4   |   |   |   | (10.5 | ) |
| Ending balance, Sep. 30                                                              |   | $                     | 6.2    |   |   | $ | 2.3 |   |
|                                                                                 |   |                  |   |   |   |   |   |   |
| The amount of total gains or (losses) for the period included in changes in net      |   |                  |   |   |   |   |   |   |
| assets attributable to the change in unrealized gains or (losses) relating to assets |   |                  |   |   |   |   |   |   |
| and liabilities held at Sep. 30 (a)                                                  |   | $                     | (4.5   | ) |   | $ | 2.3 |   |

| (a)   | Recorded in “Regulatory assets” and “Regulatory liabilities” on IPL’s Condensed Consolidated Balance Sheets. |
|-----------------|--------------------------------------------------------------------------------------------------------------------------------------------|

----

|                                |   | Electric      |    |   | Gas    |   |   | Other  |   |   | Total  |   |
|-------------------------------------|--------|---------------|---------|--------|--------|--------|--------|--------|--------|--------|--------|--------|
|                                |   | (in millions) |    |
| Three Months Ended Sep. 30, 2009    |   |          |    |   |   |   |   |   |   |   |   |   |
| Operating revenues                  |   | $             | 417.9   |   |   | $      | 22.6   |   |   | $      | 17.4   |   |   | $ | 457.9 |   |
| Operating income (loss)             |   |          | 118.2   |   |   |   | (1.0   | )      |   |   | (0.6   | )      |   |   | 116.6 |   |
| Earnings available for common stock |   |          |    |   |   |   |   |   |   |   |   |   |   |   | 69.0 |   |
|                                |   |          |    |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Three Months Ended Sep. 30, 2008    |   |          |    |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating revenues                  |   |          | 394.8   |   |   |   | 42.2   |   |   |   | 27.4   |   |   |   | 464.4 |   |
| Operating income (loss)             |   |          | 107.6   |   |   |   | (2.4   | )      |   |   | (0.5   | )      |   |   | 104.7 |   |
| Earnings available for common stock |   |          |    |   |   |   |   |   |   |   |   |   |   |   | 59.3 |   |
|                                |   |          |    |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Nine Months Ended Sep. 30, 2009     |   |          |    |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating revenues                  |   |          | 1,022.7 |   |   |   | 208.1  |   |   |   | 63.3   |   |   |   | 1,294.1 |   |
| Operating income (loss)             |   |          | 162.0   |   |   |   | 12.6   |   |   |   | (0.1   | )      |   |   | 174.5 |   |
| Earnings available for common stock |   |          |    |   |   |   |   |   |   |   |   |   |   |   | 122.4 |   |
|                                |   |          |    |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Nine Months Ended Sep. 30, 2008     |   |          |    |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating revenues                  |   |          | 973.6   |   |   |   | 292.9  |   |   |   | 56.6   |   |   |   | 1,323.1 |   |
| Operating income                    |   |          | 174.8   |   |   |   | 18.1   |   |   |   | 2.0    |   |   |   | 194.9 |   |
| Earnings available for common stock |   |          |    |   |   |   |   |   |   |   |   |   |   |   | 101.3 |   |

|                               |   | Three Months |   |   | Nine Months |   |
|------------------------------------|--------|--------------|--------|--------|-------------|--------|
|                               |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| Corporate Services billings to IPL |   | $            | 41.9   |   |        | $      | 43.0 |   |   | $ | 116.6 |   |   | $ | 141.8 |   |

----

| WISCONSIN POWER AND LIGHT COMPANY                                                                               |   |
|-----------------------------------------------------------------------------------------------------------------|--------|
| CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)                                                         |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                            |   | For the Three Months |   |   | For the Nine Months |   |
|                                                                                                            |   | Ended September 30, |   |   | Ended September 30, |   |
|                                                                                                            |   | 2009 |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |
|                                                                                                            |   | (in millions) |   |
| Operating revenues:                                                                                             |   |   |   |   |   |   |   |   |   |   |   |   |
|   Electric utility                                                                                    |   | $ | 307.4 |   |   | $ | 319.2 |   |   | $ | 878.5 |   |   | $ | 884.8 |   |
|   Gas utility                                                                                         |   |   | 16.5 |   |   |   | 31.3 |   |   |   | 153.7 |   |   |   | 210.2 |   |
|   Other                                                                                               |   |   | 2.7 |   |   |   | 3.4 |   |   |   | 6.1 |   |   |   | 7.7 |   |
|                                                                                                            |   |   | 326.6 |   |   |   | 353.9 |   |   |   | 1,038.3 |   |   |   | 1,102.7 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating expenses:                                                                                             |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|   Electric production fuel and purchased power                                                        |   |   | 166.7 |   |   |   | 156.8 |   |   |   | 467.3 |   |   |   | 452.9 |   |
|   Electric transmission service                                                                       |   |   | 23.7 |   |   |   | 23.8 |   |   |   | 70.8 |   |   |   | 71.4 |   |
|   Cost of gas sold                                                                                    |   |   | 4.9 |   |   |   | 18.7 |   |   |   | 99.3 |   |   |   | 145.7 |   |
|   Other operation and maintenance                                                                     |   |   | 49.8 |   |   |   | 51.7 |   |   |   | 165.7 |   |   |   | 164.9 |   |
|   Depreciation and amortization                                                                       |   |   | 29.8 |   |   |   | 23.5 |   |   |   | 85.0 |   |   |   | 77.1 |   |
|   Taxes other than income taxes                                                                       |   |   | 10.2 |   |   |   | 9.8 |   |   |   | 30.9 |   |   |   | 30.4 |   |
|                                                                                                            |   |   | 285.1 |   |   |   | 284.3 |   |   |   | 919.0 |   |   |   | 942.4 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating income                                                                                                |   |   | 41.5 |   |   |   | 69.6 |   |   |   | 119.3 |   |   |   | 160.3 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Interest expense and other:                                                                                     |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|   Interest expense                                                                                    |   |   | 19.9 |   |   |   | 14.7 |   |   |   | 54.6 |   |   |   | 44.5 |   |
|   Equity income from unconsolidated investments                                                       |   |   | (9.5 | ) |   |   | (9.3 | ) |   |   | (27.6 | ) |   |   | (24.9 | ) |
|   Allowance for funds used during construction                                                        |   |   | (1.3 | ) |   |   | (3.2 | ) |   |   | (2.9 | ) |   |   | (7.4 | ) |
|   Interest income and other                                                                           |   |   | (0.1 | ) |   |   | - |   |   |   | (0.3 | ) |   |   | (0.1 | ) |
|                                                                                                            |   |   | 9.0 |   |   |   | 2.2 |   |   |   | 23.8 |   |   |   | 12.1 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Income before income taxes                                                                                      |   |   | 32.5 |   |   |   | 67.4 |   |   |   | 95.5 |   |   |   | 148.2 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Income taxes                                                                                                    |   |   | 11.5 |   |   |   | 24.8 |   |   |   | 31.6 |   |   |   | 54.1 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Net income                                                                                                      |   |   | 21.0 |   |   |   | 42.6 |   |   |   | 63.9 |   |   |   | 94.1 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Preferred dividend requirements                                                                                 |   |   | 0.8 |   |   |   | 0.8 |   |   |   | 2.5 |   |   |   | 2.5 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Earnings available for common stock                                                                             |   | $ | 20.2 |   |   | $ | 41.8 |   |   | $ | 61.4 |   |   | $ | 91.6 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these statements. |   |

----

| WISCONSIN POWER AND LIGHT COMPANY                                                                               |   |
|-----------------------------------------------------------------------------------------------------------------|--------|
| CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)                                                               |   |
|                                                                                                            |   |   |   |   |   |   |
|                                                                                                            |   | September 30, |   |   | December 31, |   |
| ASSETS                                                                                                          |   | 2009 |   |   | 2008 |   |
|                                                                                                            |   | (in millions) |   |
| Property, plant and equipment:                                                                                  |   |   |   |   |   |   |
|   Electric plant in service                                                                           |   | $ | 2,737.1 |   |   | $ | 2,500.3 |   |
|   Gas plant in service                                                                                |   |   | 384.5 |   |   |   | 370.1 |   |
|   Other plant in service                                                                              |   |   | 214.2 |   |   |   | 198.1 |   |
|   Accumulated depreciation                                                                            |   |   | (1,232.6 | ) |   |   | (1,165.9 | ) |
|      Net plant                                                                         |   |   | 2,103.2 |   |   |   | 1,902.6 |   |
|   Leased Sheboygan Falls Energy Facility, less accumulated amortization                               |   |   | 97.1 |   |   |   | 101.7 |   |
|   Construction work in progress:                                                                      |   |   |   |   |   |   |   |   |
|      Bent Tree wind project                                                            |   |   | 124.3 |   |   |   | - |   |
|      Other                                                                             |   |   | 68.0 |   |   |   | 88.4 |   |
|   Other, less accumulated depreciation                                                                |   |   | 20.9 |   |   |   | 3.8 |   |
|                                                                                                            |   |   | 2,413.5 |   |   |   | 2,096.5 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Current assets:                                                                                                 |   |   |   |   |   |   |   |   |
|   Cash and cash equivalents                                                                           |   |   | 90.7 |   |   |   | 4.5 |   |
|   Accounts receivable:                                                                                |   |   |   |   |   |   |   |   |
|      Customer, less allowance for doubtful accounts                                    |   |   | 67.0 |   |   |   | 83.4 |   |
|      Unbilled utility revenues                                                         |   |   | 61.0 |   |   |   | 92.5 |   |
|      Other, less allowance for doubtful accounts                                       |   |   | 54.1 |   |   |   | 75.9 |   |
|   Income tax refunds receivable                                                                       |   |   | 63.4 |   |   |   | 8.4 |   |
|   Production fuel, at weighted average cost                                                           |   |   | 39.4 |   |   |   | 40.4 |   |
|   Materials and supplies, at weighted average cost                                                    |   |   | 22.8 |   |   |   | 22.8 |   |
|   Gas stored underground, at weighted average cost                                                    |   |   | 29.8 |   |   |   | 47.9 |   |
|   Regulatory assets                                                                                   |   |   | 51.9 |   |   |   | 21.8 |   |
|   Prepaid gross receipts tax                                                                          |   |   | 28.1 |   |   |   | 37.8 |   |
|   Derivative assets                                                                                   |   |   | 10.4 |   |   |   | 10.7 |   |
|   Other                                                                                               |   |   | 25.4 |   |   |   | 25.6 |   |
|                                                                                                            |   |   | 544.0 |   |   |   | 471.7 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Investments:                                                                                                    |   |   |   |   |   |   |   |   |
|   Investment in American Transmission Company LLC                                                     |   |   | 211.8 |   |   |   | 195.1 |   |
|   Other                                                                                               |   |   | 22.4 |   |   |   | 22.2 |   |
|                                                                                                            |   |   | 234.2 |   |   |   | 217.3 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Other assets:                                                                                                   |   |   |   |   |   |   |   |   |
|   Regulatory assets                                                                                   |   |   | 366.6 |   |   |   | 378.6 |   |
|   Deferred charges and other                                                                          |   |   | 72.1 |   |   |   | 101.4 |   |
|                                                                                                            |   |   | 438.7 |   |   |   | 480.0 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Total assets                                                                                                    |   | $ | 3,630.4 |   |   | $ | 3,265.5 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these statements. |   |

----

| WISCONSIN POWER AND LIGHT COMPANY                                                                               |   |
|-----------------------------------------------------------------------------------------------------------------|--------|
| CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Continued)                                                   |   |
|                                                                                                            |   |   |   |   |   |   |
|                                                                                                            |   | September 30, |   |   | December 31, |   |
| CAPITALIZATION AND LIABILITIES                                                                                  |   | 2009 |   |   | 2008 |   |
|                                                                                                            |   | (in millions, except per |   |
|                                                                                                            |   | share and share amounts) |   |
| Capitalization:                                                                                                 |   |   |   |   |   |   |
|   Wisconsin Power and Light Company common equity:                                                    |   |   |   |   |   |   |
|      Common stock - $5 par value - authorized 18,000,000 shares;                            |   |   |   |   |
|        13,236,601 shares outstanding                                         |   | $ | 66.2 |   |   | $ | 66.2 |   |
|      Additional paid-in capital                                                        |   |   | 768.9 |   |   |   | 668.9 |   |
|      Retained earnings                                                                 |   |   | 417.6 |   |   |   | 424.4 |   |
|        Total Wisconsin Power and Light Company common equity                 |   |   | 1,252.7 |   |   |   | 1,159.5 |   |
|   Cumulative preferred stock                                                                          |   |   | 60.0 |   |   |   | 60.0 |   |
|   Long-term debt, net (excluding current portion)                                                     |   |   | 931.5 |   |   |   | 782.9 |   |
|                                                                                                            |   |   | 2,244.2 |   |   |   | 2,002.4 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Current liabilities:                                                                                            |   |   |   |   |   |   |   |   |
|   Current maturities of long-term debt                                                                |   |   | 100.0 |   |   |   | - |   |
|   Commercial paper                                                                                    |   |   | - |   |   |   | 43.7 |   |
|   Accounts payable                                                                                    |   |   | 101.4 |   |   |   | 130.9 |   |
|   Accounts payable to associated companies                                                            |   |   | 22.2 |   |   |   | 26.1 |   |
|   Accrued interest                                                                                    |   |   | 17.0 |   |   |   | 17.9 |   |
|   Regulatory liabilities                                                                              |   |   | 16.2 |   |   |   | 50.9 |   |
|   Derivative liabilities                                                                              |   |   | 34.8 |   |   |   | 8.6 |   |
|   Other                                                                                               |   |   | 37.8 |   |   |   | 26.4 |   |
|                                                                                                            |   |   | 329.4 |   |   |   | 304.5 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Other long-term liabilities and deferred credits:                                                               |   |   |   |   |   |   |   |   |
|   Deferred income taxes                                                                               |   |   | 428.5 |   |   |   | 329.3 |   |
|   Regulatory liabilities                                                                              |   |   | 168.2 |   |   |   | 174.1 |   |
|   Capital lease obligations - Sheboygan Falls Energy Facility                                         |   |   | 111.2 |   |   |   | 113.4 |   |
|   Pension and other benefit obligations                                                               |   |   | 168.7 |   |   |   | 185.1 |   |
|   Other                                                                                               |   |   | 180.2 |   |   |   | 156.7 |   |
|                                                                                                            |   |   | 1,056.8 |   |   |   | 958.6 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Total capitalization and liabilities                                                                            |   | $ | 3,630.4 |   |   | $ | 3,265.5 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these statements. |   |

----

| WISCONSIN POWER AND LIGHT COMPANY                                                                               |   |
|-----------------------------------------------------------------------------------------------------------------|--------|
| CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)                                                     |   |
|                                                                                                            |   |   |   |   |   |   |
|                                                                                                            |   | For the Nine Months Ended September 30, |   |
|                                                                                                            |   | 2009 |   |   | 2008 |   |
|                                                                                                            |   | (in millions) |   |
| Cash flows from operating activities:                                                                           |   |   |   |   |   |   |
|   Net income                                                                                          |   | $ | 63.9 |   |   | $ | 94.1 |   |
|   Adjustments to reconcile net income to net cash flows from operating activities:                    |   |
|      Depreciation and amortization                                                     |   |   | 85.0 |   |   |   | 77.1 |   |
|      Other amortizations                                                               |   |   | 26.3 |   |   |   | 28.8 |   |
|      Deferred tax expense and investment tax credits                                   |   |   | 102.6 |   |   |   | 18.0 |   |
|      Equity income from unconsolidated investments                                     |   |   | (27.6 | ) |   |   | (24.9 | ) |
|      Distributions from equity method investments                                      |   |   | 22.4 |   |   |   | 20.9 |   |
|      Other                                                                             |   |   | (2.0 | ) |   |   | (5.3 | ) |
|   Other changes in assets and liabilities:                                                            |   |   |   |   |   |   |   |   |
|      Accounts receivable                                                               |   |   | 62.7 |   |   |   | 17.7 |   |
|      Income tax refunds receivable                                                     |   |   | (55.0 | ) |   |   | 2.6 |   |
|      Gas stored underground                                                            |   |   | 18.1 |   |   |   | (11.9 | ) |
|      Regulatory assets                                                                 |   |   | (42.6 | ) |   |   | 1.4 |   |
|      Accounts payable                                                                  |   |   | (15.1 | ) |   |   | 33.3 |   |
|      Accounts payable to associated companies                                          |   |   | (3.9 | ) |   |   | (29.1 | ) |
|      Regulatory liabilities                                                            |   |   | (31.6 | ) |   |   | (6.1 | ) |
|      Derivative liabilities                                                            |   |   | 34.3 |   |   |   | (2.8 | ) |
|      Non-current taxes payable                                                         |   |   | 21.6 |   |   |   | (0.7 | ) |
|      Pension and other benefit obligations                                             |   |   | (16.4 | ) |   |   | (4.5 | ) |
|      Other                                                                             |   |   | 13.4 |   |   |   | 3.7 |   |
|        Net cash flows from operating activities                              |   |   | 256.1 |   |   |   | 212.3 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Cash flows used for investing activities:                                                                       |   |   |   |   |   |   |   |   |
|      Utility construction and acquisition expenditures:                                |   |   |   |   |   |   |   |   |
|        Neenah Energy Facility and related assets                             |   |   | (92.4 | ) |   |   | - |   |
|        Other                                                                 |   |   | (324.0 | ) |   |   | (262.7 | ) |
|      Advances for customer energy efficiency projects                                  |   |   | (19.1 | ) |   |   | (16.8 | ) |
|      Collections of advances for customer energy efficiency projects                   |   |   | 50.0 |   |   |   | 28.3 |   |
|      Other                                                                             |   |   | (11.2 | ) |   |   | 3.5 |   |
|        Net cash flows used for investing activities                          |   |   | (396.7 | ) |   |   | (247.7 | ) |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Cash flows from financing activities:                                                                           |   |   |   |   |   |   |   |   |
|      Common stock dividends                                                            |   |   | (68.2 | ) |   |   | (22.8 | ) |
|      Preferred stock dividends                                                         |   |   | (2.5 | ) |   |   | (2.5 | ) |
|      Capital contribution from parent                                                  |   |   | 100.0 |   |   |   | 100.0 |   |
|      Proceeds from issuance of long-term debt                                          |   |   | 250.0 |   |   |   | - |   |
|      Net change in short-term borrowings                                               |   |   | (43.7 | ) |   |   | (22.7 | ) |
|      Changes in cash overdrafts                                                        |   |   | (3.1 | ) |   |   | (13.1 | ) |
|      Other                                                                             |   |   | (5.7 | ) |   |   | (2.2 | ) |
|        Net cash flows from financing activities                              |   |   | 226.8 |   |   |   | 36.7 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Net increase in cash and cash equivalents                                                                       |   |   | 86.2 |   |   |   | 1.3 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Cash and cash equivalents at beginning of period                                                                |   |   | 4.5 |   |   |   | 0.4 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Cash and cash equivalents at end of period                                                                      |   | $ | 90.7 |   |   | $ | 1.7 |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| Supplemental cash flows information:                                                                            |   |   |   |   |   |   |   |   |
|   Cash paid (refunded) during the period for:                                                         |   |   |   |   |   |   |   |   |
|     Interest                                                                                |   | $ | 56.5 |   |   | $ | 49.9 |   |
|     Income taxes, net of refunds                                                            |   | $ | (36.2 | ) |   | $ | 20.7 |   |
|   Noncash investing and financing activities:                                                         |   |   |   |   |   |   |   |   |
|     Capital lease obligations incurred                                                      |   | $ | 0.7 |   |   | $ | - |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
|                                                                                                            |   |   |   |   |   |   |   |   |
| The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these statements. |   |

----

|                                   |   | Qualified Pension Benefits |   |   | Other Postretirement Benefits |   |
|----------------------------------------|--------|----------------------------|--------|--------|-------------------------------|--------|
|                                   |   | Three Months               |   |   | Nine Months                   |   |   | Three Months |   |   | Nine Months |   |
|                                   |   | 2009                       |   |   | 2008                          |   |   | 2009 |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |
| Service cost                           |   | $                          | 1.3    |   |                          | $      | 1.3 |   |   | $ | 3.9 |   |   | $ | 4.0 |   |   | $ | 0.8 |   |   | $ | 0.8 |   |   | $ | 2.5 |   |   | $ | 2.4 |   |
| Interest cost                          |   |                       | 3.9    |   |                          |   | 3.8 |   |   |   | 11.7 |   |   |   | 11.3 |   |   |   | 1.3 |   |   |   | 1.3 |   |   |   | 4.1 |   |   |   | 4.1 |   |
| Expected return on plan assets         |   |                       | (3.5   | )      |                          |   | (5.4 | ) |   |   | (10.5 | ) |   |   | (16.1 | ) |   |   | (0.2 | ) |   |   | (0.5 | ) |   |   | (0.8 | ) |   |   | (1.4 | ) |
| Amortization of:                       |   |                       |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Prior service cost (credit)            |   |                       | 0.1    |   |                          |   | 0.2 |   |   |   | 0.4 |   |   |   | 0.6 |   |   |   | (0.2 | ) |   |   | (0.2 | ) |   |   | (0.7 | ) |   |   | (0.7 | ) |
| Actuarial loss                         |   |                       | 2.8    |   |                          |   | 0.3 |   |   |   | 8.5 |   |   |   | 0.8 |   |   |   | 0.3 |   |   |   | 0.3 |   |   |   | 1.0 |   |   |   | 0.8 |   |
| Curtailment loss (a)                   |   |                       | --     |   |                          |   | -- |   |   |   | 0.7 |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |
| Special termination benefits costs (b) |   |                       | --     |   |                          |   | -- |   |   |   | 0.5 |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |
|                                   |   | $                          | 4.6    |   |                          | $      | 0.2 |   |   | $ | 15.2 |   |   | $ | 0.6 |   |   | $ | 2.0 |   |   | $ | 1.7 |   |   | $ | 6.1 |   |   | $ | 5.2 |   |

| (a)   | Refer to Note 6(a) of Alliant Energy’s “Notes to Condensed Consolidated Financial Statements” for details on the $0.7 million one-time curtailment loss recognized by WPL in the second quarter of 2009. |
|-----------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| (b)   | For the nine months ended Sep. 30, 2009, WPL recognized special termination benefits costs of $0.5 million related to the bargaining unit pension plan that is sponsored by WPL as a result of the elimination of certain operations positions in the second quarter of 2009. |
|-----------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

|                              |   | Pension Benefits |   |   | Other Postretirement Benefits |   |
|-----------------------------------|--------|------------------|--------|--------|-------------------------------|--------|
|                              |   | Three Months     |   |   | Nine Months                   |   |   | Three Months |   |   | Nine Months |   |
|                              |   | 2009             |   |   | 2008                          |   |   | 2009 |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |
| Non-bargaining WPL employees      |   |             |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| participating in other plans      |   | $                | 0.8    |   |                          | $      | (0.7 | ) |   | $ | 2.5 |   |   | $ | (2.2 | ) |   |   | N/A |   |   |   | N/A |   |   |   | N/A |   |   |   | N/A |   |
| Allocated Corporate Service costs |   |             | 0.3    |   |                          |   | 0.1 |   |   |   | 0.8 |   |   |   | 0.5 |   |   | $ | 0.3 |   |   | $ | 0.2 |   |   | $ | 0.9 |   |   | $ | 0.7 |   |

|                   |   |         |   |   |    |   |   |    |   |   |    |   |
|------------------------|--------|--------------|--------|--------|---------|--------|--------|---------|--------|--------|---------|--------|
|                   |   | Fair Value   |   |   |    |   |   |    |   |   |    |   |
|                   |   | Measurements |   |   | Level 1 |   |   | Level 2 |   |   | Level 3 |   |
| Sep. 30, 2009          |   |         |   |   |    |   |   |    |   |   |    |   |
| Derivative assets      |   | $            | 14.6   |   |    | $      | --     |    |   | $      | 8.9     |   |   | $ | 5.7 |   |
| Derivative liabilities |   |         | 49.1   |   |    |   | --     |    |   |   | 45.8    |   |   |   | 3.3 |   |
|                   |   |         |   |   |    |   |   |    |   |   |    |   |   |   |   |   |
| Dec. 31, 2008          |   |         |   |   |    |   |   |    |   |   |    |   |   |   |   |   |
| Derivative assets      |   |         | 19.6   |   |    |   | --     |    |   |   | 1.0     |   |   |   | 18.6 |   |
| Derivative liabilities |   |         | 14.8   |   |    |   | --     |    |   |   | 10.6    |   |   |   | 4.2 |   |

|                                                                                 |   | Derivative Assets and |   |
|--------------------------------------------------------------------------------------|--------|-----------------------|--------|
|                                                                                 |   | Liabilities, net      |   |
| Three months ended Sep. 30                                                           |   | 2009                  |   |   | 2008 |   |
| Beginning balance, July 1                                                            |   | $                     | (3.5   | ) |   | $ | 18.4 |   |
| Total gains or (losses) (realized/unrealized) included in changes in net assets (a)  |   |                  | --     |   |   |   | 7.9 |   |
| Purchases, sales, issuances and settlements, net                                     |   |                  | (1.1   | ) |   |   | (6.2 | ) |
| Transfers in and/or out of Level 3                                                   |   |                  | 7.0    |   |   |   | -- |   |
| Ending balance, Sep. 30                                                              |   | $                     | 2.4    |   |   | $ | 20.1 |   |
|                                                                                 |   |                  |   |   |   |   |   |   |
| The amount of total gains or (losses) for the period included in changes in net      |   |                  |   |   |   |   |   |   |
| assets attributable to the change in unrealized gains or (losses) relating to assets |   |                  |   |   |   |   |   |   |
| and liabilities held at Sep. 30 (a)                                                  |   | $                     | --     |   |   | $ | 7.5 |   |
|                                                                                 |   |                  |   |   |   |   |   |   |
| Nine months ended Sep. 30                                                            |   |                  |   |   |   |   |   |   |
| Beginning balance, Jan. 1                                                            |   | $                     | 14.4   |   |   | $ | 12.7 |   |
| Total gains or (losses) (realized/unrealized) included in changes in net assets (a)  |   |                  | (0.5   | ) |   |   | 19.3 |   |
| Purchases, sales, issuances and settlements, net                                     |   |                  | (11.5  | ) |   |   | (11.9 | ) |
| Ending balance, Sep. 30                                                              |   | $                     | 2.4    |   |   | $ | 20.1 |   |
|                                                                                 |   |                  |   |   |   |   |   |   |
| The amount of total gains or (losses) for the period included in changes in net      |   |                  |   |   |   |   |   |   |
| assets attributable to the change in unrealized gains or (losses) relating to assets |   |                  |   |   |   |   |   |   |
| and liabilities held at Sep. 30 (a)                                                  |   | $                     | --     |   |   | $ | 20.1 |   |

| (a)   | Recorded in “Regulatory assets” and “Regulatory liabilities” on WPL’s Condensed Consolidated Balance Sheets. |
|-----------------|--------------------------------------------------------------------------------------------------------------------------------------------|

----

|                                |   | Electric      |   |   | Gas    |   |   | Other  |   |   | Total  |   |
|-------------------------------------|--------|---------------|--------|--------|--------|--------|--------|--------|--------|--------|--------|--------|
|                                |   | (in millions) |   |
| Three Months Ended Sep. 30, 2009    |   |          |   |   |   |   |   |   |   |   |   |   |
| Operating revenues                  |   | $             | 307.4  |   |   | $      | 16.5   |   |   | $      | 2.7    |   |   | $ | 326.6 |   |
| Operating income (loss)             |   |          | 43.3   |   |   |   | (1.5   | )      |   |   | (0.3   | )      |   |   | 41.5 |   |
| Earnings available for common stock |   |          |   |   |   |   |   |   |   |   |   |   |   |   | 20.2 |   |
|                                |   |          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Three Months Ended Sep. 30, 2008    |   |          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating revenues                  |   |          | 319.2  |   |   |   | 31.3   |   |   |   | 3.4    |   |   |   | 353.9 |   |
| Operating income                    |   |          | 67.0   |   |   |   | 1.0    |   |   |   | 1.6    |   |   |   | 69.6 |   |
| Earnings available for common stock |   |          |   |   |   |   |   |   |   |   |   |   |   |   | 41.8 |   |
|                                |   |          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Nine Months Ended Sep. 30, 2009     |   |          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating revenues                  |   |          | 878.5  |   |   |   | 153.7  |   |   |   | 6.1    |   |   |   | 1,038.3 |   |
| Operating income (loss)             |   |          | 105.7  |   |   |   | 14.3   |   |   |   | (0.7   | )      |   |   | 119.3 |   |
| Earnings available for common stock |   |          |   |   |   |   |   |   |   |   |   |   |   |   | 61.4 |   |
|                                |   |          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Nine Months Ended Sep. 30, 2008     |   |          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating revenues                  |   |          | 884.8  |   |   |   | 210.2  |   |   |   | 7.7    |   |   |   | 1,102.7 |   |
| Operating income                    |   |          | 132.0  |   |   |   | 27.2   |   |   |   | 1.1    |   |   |   | 160.3 |   |
| Earnings available for common stock |   |          |   |   |   |   |   |   |   |   |   |   |   |   | 91.6 |   |

|                               |   | Three Months |   |   | Nine Months |   |
|------------------------------------|--------|--------------|--------|--------|-------------|--------|
|                               |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| Corporate Services billings to WPL |   | $            | 28.7   |   |        | $      | 32.6 |   |   | $ | 86.1 |   |   | $ | 88.1 |   |

----

|  Alliant Energy                    |
|-----------------------------------------|
|                                    |   |   |   |   |
| Utility                                 |   | Non-regulated (Resources) |   | Parent and Other |
| - IPL (Utility services in IA & MN) |   | - RMT (including WindConnect®) |   | - Parent Company |
| - WPL (Utility services in WI)          |   | - Transportation |   | - Corporate Services |
| - WPL’s interest in ATC           |   | - Non-regulated Generation |   |   |

|                                     |   | 2009   |   |   | 2008   |   |
|------------------------------------------|--------|--------|--------|--------|--------|--------|
|                                     |   | Income |   |   |   |   |   | Income |   |   |   |   |
|                                     |   | (Loss) |   |   | EPS    |   |   | (Loss) |   |   | EPS |   |
| Continuing operations:                   |   |   |   |   |   |   |   |   |   |   |   |   |
| Utility                                  |   | $      | 89.2   |   |   | $      | 0.81 |   |   | $ | 101.1 |   |   | $ | 0.92 |   |
| Non-regulated (Resources)                |   |   | 1.3    |   |   |   | 0.01 |   |   |   | 7.1 |   |   |   | 0.06 |   |
| Parent company and other                 |   |   | (133.8 | )      |   |   | (1.21 | ) |   |   | 0.9 |   |   |   | 0.01 |   |
| Income (loss) from continuing operations |   |   | (43.3  | )      |   |   | (0.39 | ) |   |   | 109.1 |   |   |   | 0.99 |   |
| Loss from discontinued operations        |   |   | (1.0   | )      |   |   | (0.01 | ) |   |   | (0.6 | ) |   |   | (0.01 | ) |
| Total                                    |   | $      | (44.3  | )      |   | $      | (0.40 | ) |   | $ | 108.5 |   |   | $ | 0.98 |   |

| ·   | impacts on retail electric sales of extremely cool weather during the summer of 2009; and |
|--------------------|-------------------------------------------------------------------------------------------|

| ·   | lower electric sales from industrial and wholesale customers resulting from unfavorable economic conditions. |
|--------------------|--------------------------------------------------------------------------------------------------------------|

----

| ·   | impacts from the interim electric retail rate increase at IPL effective in late March 2009; and |
|--------------------|-------------------------------------------------------------------------------------------------|

| ·   | impacts from the severe Midwest flooding in June 2008. |
|--------------------|--------------------------------------------------------|

| ·   | March 2009 - IPL announced a decision to cancel the construction of Sutherland #4. |
|--------------------|------------------------------------------------------------------------------------|

| ·   | March 2009 - WPL acquired approximately 400 MW of wind site capacity in Freeborn County, Minnesota and the development rights for an approximately 100 MW wind project site near Green Lake, Wisconsin.  WPL plans to use 200 MW of the capacity from the wind project site in Freeborn County, Minnesota for its Bent Tree wind project. |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | April 2009 - WPL filed a construction application with the PSCW to install emission controls at Columbia to reduce SO2 and mercury emissions. |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | May 2009 - WPL decided to cease operations by the end of 2009 at the four gas-fired electric generating units known as Rock River units 1 and 2 and Blackhawk units 3 and 4. |
|--------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | June 2009 - WPL acquired the Neenah Energy Facility and related assets from Resources for $92 million. |
|--------------------|--------------------------------------------------------------------------------------------------------|

| ·   | July 2009 - WPL received an order from the PSCW approving construction of the 200 MW Bent Tree wind project. |
|--------------------|--------------------------------------------------------------------------------------------------------------|

| ·   | August 2009 - IPL announced plans to utilize 100 MW of wind turbine generator sets and related equipment under the master supply agreement entered into with Vestas in June 2008 for future development of the second phase of the Whispering Willow wind project, known as the Whispering Willow - West wind project. |
|--------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | August 2009 - Alliant Energy announced an updated multi-emission compliance plan capital expenditures forecast, which decreased by $5 million, $130 million and $165 million for 2009, 2010 and 2011, respectively, compared to what was reported in the 2008 Form 10-K. |
|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | October 2009 - WPL received an order from the MPUC approving the Site Permit and Certificate of Need applications for the 200 MW Bent Tree wind project. |
|--------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | February 2009 - The ARRA was enacted.  The most significant provisions of the ARRA for Alliant Energy, IPL and WPL provide a one-year extension of the 50% bonus depreciation deduction for certain expenditures for property that is acquired or constructed in 2009, incentives for wind facilities placed in service by Dec. 31, 2012 and grants forqualifying investments that are expected to improve the electric grid and transportation infrastructure. |
|--------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | February 2009 - SB 62 was enacted.  The most significant provision of SB 62 for Alliant Energy, IPL and WPL requires combined reporting for corporate income taxation in Wisconsin beginning with tax returns filed for the calendar year 2009. |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

| ·   | March 2009 - IPL filed a request with the IUB to increase annual electric rates for its Iowa retail customers by $171 million, or approximately 17%.  The filing is based on a 2008 historical test year.  The request includes a return on common equity of 11.4% and a capital structure with 48.5% common equity, 44.4% long-term debt and7.1% preferred stock.  An interim retail rate increase of $84 million, or approximately 8% on an annual basis, was implemented effective March 27, 2009 without regulatory review and will be subject to refund pending determination of final rates.  Any final rate changes are expected to be effective in the first quarter of 2010.  In September 2009, IPL revised this request to seek an increase of $146 million, or approximately 14%.  The decrease in the requested amount wasprimarily due to an alternative cost recovery process on the capital expenditures for Sutherland #4 and an alternative method (five-year average) for calculating the annual recovery amount of pension and other postretirement benefits costs. |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | April 2009 - The PSCW issued an order granting WPL’s request to refund to its retail electric customers in the second quarter of 2009 the remaining $5 million related to the 2008 fuel-related retail rate case and the remaining $2 million related to fuel-related costs in the 2007 retail rate case. |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | April 2009 - WPL executed an agreement with its wholesale customers to recover $4 million of the wholesale portion of the capitalized expenditures incurred for the Nelson Dewey #3 project.  WPL is currently recovering $4 million of capitalized expenditures from its wholesale customers over a one-year period ending May 2010. |
|--------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | May 2009 - WPL filed a request with the PSCW to increase annual retail electric rates by $86 million, or approximately 9%, and increase annual retail natural gas rates by $6 million, or approximately 3%.  Any rate changes granted are expected to be effective in January 2010.  The request is based on a 2010 forward-looking test yearand includes a return on common equity of 10.6% and a capital structure with 53.5% common equity, 41.6% long-term debt, 2.5% short-term debt and 2.4% preferred equity.  In addition, WPL requested recovery of the remaining retail portion of the Nelson Dewey #3 costs over a five-year period ending December 2014.  In September 2009, WPL revised its annual retail electric rate increase request to $99 million and its annual retail natural gas rate increase request to $8 million.  Theincrease in the requested amount for the retail electric rates was primarily due to a reduced 2010 sales forecast. |
|--------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | June 2009 - The IUB issued an order allowing IPL to use a portion of the refund account established with the sale of IPL’s electric transmission assets to reduce customers’ rates by $12 million for the period from July 2009 through February 2010. |
|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | June 2009 - The U.S. House of Representatives approved H.R. 2454.  H.R. 2454 contains a proposed cap-and-trade GHG emissions reduction program, and renewable electricity standard and energy efficiency requirements by 2020. |
|--------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | July 2009 - Iowa’s Office of Consumer Advocate (OCA) filed a request with the IUB to decrease annual electric rates for IPL’s Iowa retail customers by $30 million, or approximately 3%.  The primary difference between the OCA’s request and the latest request by IPL relates to recovery of increased costs for transmission service. |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | August 2009 - WPL filed a request with the PSCW to set its retail electric fuel cost collections subject to refund.  In September 2009, the PSCW set WPL’s retail electric fuel rates currently in effect subject to refund for the period from Sep. 1, 2009 until the date the next fuel-related order issued by the PSCW is effective. |
|--------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | September 2009 - The PSCW staff recommended to the PSCW rate increases for 2010 of $73 million for WPL’s retail electric rates and $5 million for WPL’s retail natural gas rates.  The primary differences between the rate increases recommended by the PSCW staff and the latest rate increases requested by WPL relate to the impact of areduced 2010 sales forecast filed by WPL in the third quarter of 2009 and different capital structures. |
|--------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | September 2009 - S. 1733 was introduced, which is currently expected to be the primary bill for the U.S. Senate’s action on climate change.  Unlike H.R. 2454, S. 1733 focuses only on the cap-and-trade program and does not include energy efficiency requirements, a renewable electricity standard or other energy-related items. |
|--------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | March 2009 - Alliant Energy, IPL and WPL amended their respective credit facility agreements to release Lehman from the agreements.  The three amended credit facilities total $623 million ($96 million for Alliant Energy at the parent company level, $287 million for IPL and $240 million for WPL). |
|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

| ·   | June 2009 - IPL’s and WPL’s respective shelf registration statements became effective, which provided IPL and WPL the flexibility to offer up to an aggregate of $650 million and $700 million, respectively, of preferred stock and unsecured debt securities from June 2009 through June 2012. |
|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | June 2009 - IPL received approval from the MPUC for its annual capital structure filing, which provides authorization for IPL to issue debt securities during the 12 months ended June 30, 2010 as long as IPL maintains a common equity ratio between 41.3% and 50.5% during such period.  The annual capital structure filing limits IPL’s short-termborrowings to a maximum of $300 million outstanding at any time during the 12 months ended June 30, 2010. |
|--------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | July 2009 - WPL received authorization from the PSCW to issue unsecured indebtedness of no more than $350 million in each of 2009 and 2010, with a total not to exceed $600 million. |
|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | July 2009 - IPL issued $300 million of 6.25% senior debentures due 2039 and WPL issued $250 million of 5.00% debentures due 2019.  The proceeds from these debt issuances were used initially to repay short-term debt and invest in short-term assets. |
|--------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | August 2009 - IPL redeemed $135 million of its 6.625% senior debentures. |
|--------------------|--------------------------------------------------------------------------|

| ·   | August 2009 - Alliant Energy announced an updated capital expenditures forecast, which reduced anticipated capital expenditures by $100 million, $620 million and $420 million for 2009, 2010 and 2011, respectively, compared to those reported in the 2008 Form 10-K. |
|--------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | September 2009 - At Sep. 30, 2009, Alliant Energy and its subsidiaries had $623 million of available capacity under their revolving credit facilities and $177 million of cash and cash equivalents. |
|--------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | September 2009 - Alliant Energy’s shelf registration became effective, which provides Alliant Energy flexibility to offer from time to time an indeterminate amount of common stock, senior notes and other securities from September 2009 through September 2012. |
|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | September 2009 - Alliant Energy entered into a term loan facility to provide short-term financing for the repurchase of its Exchangeable Senior Notes due 2030 (Notes).  As of Sep. 30, 2009, Alliant Energy borrowed $170 million under the facility.  In October 2009, Alliant Energy repaid the $170 million of borrowings and the facilitywas terminated. |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | September 2009 - Alliant Energy announced a tender offer and consent solicitation for its Notes. As of Sep. 30, 2009, Alliant Energy had received valid tenders and consents from holders of $402.3 million aggregate principal amount of Notes (or 5,938,660 Notes), which represented 99.96% of the $402.5 million aggregate principal amount of thenoutstanding Notes (or 5,940,960 Notes).  In September 2009, Alliant Energy made $241 million of payments to repurchase the Notes.  In October 2009, Alliant Energy received valid tenders and consents from holders of $0.1 million aggregate principal amount of Notes (or 2,000 Notes).  Upon completion of the tender offer in October 2009, there were 300 Notes outstanding. |
|--------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | September 2009 - Moody’s Investors Service assigned a rating of Baa1 for Alliant Energy’s senior unsecured long-term debt and withdrew the rating for Resources’ senior unsecured long-term debt due to the repurchase of the Notes. |
|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | October 2009 - Alliant Energy issued $250 million of 4.00% senior notes due 2014 and used the proceeds to repay $170 million borrowed under the term loan facility and the remainder for general corporate purposes. |
|--------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | October 2009 - IPL filed an application with FERC for authorization to issue up to $900 million of long-term debt securities, $750 million of short-term debt securities and $200 million of preferred stock for a period from January 2010 through December 2011. |
|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | April 2009 - The EPA issued a proposed rule to require reporting of GHG emissions for facilities that emit 25,000 metric tons or more of carbon dioxide (CO2) emissions annually.  The EPA also issued a proposal that finds that concentrations of GHG emission in the atmosphere threaten public health and welfare and that emissions from motor vehiclescontribute to atmospheric concentrations of GHG emissions and hence to the threat of climate change.   |
|--------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

| ·   | May 2009 - Alliant Energy committed to participate in Phase II of the Chicago Climate Exchange for the period from 2007 through 2010. |
|--------------------|---------------------------------------------------------------------------------------------------------------------------------------|

| ·   | May 2009 - The Wisconsin Natural Resources Board approved the Wisconsin Department of Natural Resources (DNR) rule regarding the amount of heat that WPL’s generating facilities can discharge into Wisconsin waters. |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | September 2009 - The EPA issued a proposed rule to require large facilities to obtain permits that demonstrate use of the Best Available Control Technologies and energy efficiency measures to minimize GHG emissions when facilities are constructed or significantly modified. |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | October 2009 - WPL received from the Sierra Club a notice of intent to file a civil lawsuit based on allegations that major modifications were made at Nelson Dewey and Columbia without complying with the Prevention of Significant Deterioration (PSD) and Title V Operating Permit requirements of the CAA.  The allegations suggest that PSD permitsthat imposed Best Available Control Technology limits on emissions from the facilities should have been obtained for Nelson Dewey and Columbia. |
|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

| Primary     |                     |   |     |   |   | Expected     |           |   |         |   |       | Current     |   | Actual / Expected |
|-------------|--------------------------|--------|----------|--------|--------|--------------|----------------|--------|--------------|--------|------------|-------------|--------|-------------------|
| Generation  | Project Name /           |   | Capacity |   |   | Availability |           |   | Cost         |   |       | Capitalized |   | Regulatory        |
| Type        | Location                 |   | (MW)     |   |   | Date         |           |   | Estimate (a) |   |       | Costs (b)   |   | Decision Date     |
| IPL:        |                     |   |     |   |   |         |           |   |         |   |       |        |   |              |
| Wind        | Whispering Willow - East |   |     | 200    |   |         | Fourth quarter |   |         | $      | 450 - $475 |        |   | $                 | 423 |   | February 2008 |
|        | Franklin County, IA      |   |     |   |   |         | of 2009        |   |         |   |       |        |   |              |   |   |   |
|        |                     |   |     |   |   |         |           |   |         |   |       |        |   |              |   |   |   |
| Wind        | Whispering Willow - West |   |     | 100    |   |         |           | 2011   |         |   |       | 250 - 300   |   |              |   | 6 |   | TBD |
|        | Franklin County, IA      |   |     |   |   |         |           |   |         |   |       |        |   |              |   |   |   |   |
|        |                     |   |     |   |   |         |           |   |         |   |       |        |   |              |   |   |   |   |
| WPL:        |                     |   |     |   |   |         |           |   |         |   |       |        |   |              |   |   |   |   |
| Wind        | Bent Tree                |   |     | 200    |   |         |           | 2011   |         |   |       | 425 - 460   |   |              |   | 123 |   | October 2009 |
|        | Freeborn County, MN      |   |     |   |   |         |           |   |         |   |       |        |   |              |   |   |   |   |
|        |                     |   |     |   |   |         |           |   |         |   |       |        |   |              |   |   |   |   |
| Natural-gas | Riverside Energy Center  |   |     | 600    |   |         |           | 2013   |         |   |       | 365 - 375   |   |              |   | N/A |   | 2012 - 2013 |
|        | Beloit, WI               |   |     |   |   |         |           |   |         |   |       |        |   |              |   |   |   |   |
|        |                     |   |     |   |   |         |           |   |         |   |       |        |   |              | $ | 552 |   |   |

| (a)   | Cost estimates represent IPL’s or WPL’s estimated portion of the total escalated construction and acquisition expenditures in millions of dollars and exclude AFUDC, if applicable. |
|-----------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| (b)   | Costs represent capitalized expenditures in millions recorded in “Property, plant and equipment” on the respective Condensed Consolidated Balance Sheets as of Sep. 30, 2009 and exclude AFUDC, if applicable. |
|-----------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

| Emissions Controlled | Primary Technology            |   | 2009   |   |   | 2010   |   |   | 2011   |   |
|----------------------|-------------------------------|--------|--------|--------|--------|--------|--------|--------|--------|--------|
| IPL:                 |                          |   |   |   |   |   |   |   |   |   |
| Mercury              | Baghouse/Carbon Injection     |   | $      | 65     |   |   | $      | 35     |   |   | $ | 25 |   |
| NOx                  | Selective Catalytic Reduction |   |   | 50     |   |   |   | 15     |   |   |   | -- |   |
|                 |                          |   |   | 115    |   |   |   | 50     |   |   |   | 25 |   |
| WPL:                 |                          |   |   |   |   |   |   |   |   |   |   |   |   |
| Mercury              | Baghouse/Carbon Injection     |   |   | 5      |   |   |   | 20     |   |   |   | 70 |   |
| NOx                  | Selective Catalytic Reduction |   |   | 10     |   |   |   | 25     |   |   |   | 85 |   |
| SO2                  | Scrubber                      |   |   | --     |   |   |   | 15     |   |   |   | 45 |   |
|                 |                          |   |   | 15     |   |   |   | 60     |   |   |   | 200 |   |
| Alliant Energy       |                          |   | $      | 130    |   |   | $      | 110    |   |   | $ | 225 |   |

|              |   |    |   |   |   |      |   |   |        |   |   |      |   |       |   | Expected/ |    |   |
|-------------------|--------|---------|--------|--------|--------|-----------|--------|--------|-------------|--------|--------|-----------|--------|------------|--------|-----------|---------|--------|
|              |   |    |   |   |   |      |   |   |        |   |   |      |   | Final      |   | Actual    |    | Return |
|              |   |    |   |   |   | Original  |   |   | Interim     |   |   | Interim   |   | Increase   |   | Final     |    | on     |
|              |   | Utility |   | Filing |   | Increase  |   |   | Increase    |   |   | Effective |   | (Decrease) |   | Effective |    | Common |
| Rate Case         |   | Type    |   | Date   |   | Requested |   |   | Implemented |   |   | Date      |   | Granted    |   | Date      |    | Equity |
| IPL:              |   |    |   |   |   |      |   |   |        |   |   |      |   |       |   |      |    |   |
| 2009 Iowa Retail  |   |    | E      |   | Mar-09 |      | $      | 171    | (b)         |   | $      | 84        | (a)    |       | Mar-09 |      | TBD (a) |   | Q1-10 |   | TBD |
| WPL:              |   |    |   |   |   |      |   |   |        |   |   |      |   |       |   |      |    |   |   |   |   |
| 2010 Retail       |   |    | E/G    |   | May-09 |      |   | 92     | (b)         |   |   | N/A       |   |       |   | N/A       |    | TBD    |   | Jan-10 |   | TBD |
| 2008 Retail (F-R) |   |    | E      |   | Mar-08 |      |   | 16     |        |   |   | 16        |   |       | Apr-08 |      | N/A     |   | N/A |   | N/A |
| 2009/2010 Retail  |   |    | E/G    |   | Feb-08 |      |   | 92     |        |   |   | N/A       |   |       |   | N/A       |    | ($4)   |   | Jan-09 |   | N/A |

| (a)   | Interim rate relief is implemented without regulatory review, subject to refund, pending determination of final rates.  The amount of the interim retail rate increase will be replaced by the amount of final rates once the final rates are granted. |
|-----------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| (b)   | Increase requested has changed subsequent to original filing.  Refer to “IPL’s 2009 Iowa Retail Rate Case” and “WPL’s 2010 Retail Rate Case” below for additional information. |
|-----------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

----

----

----

----

|                             |   | Revenues and Costs (dollars in millions) |   |   | MWhs Sold (MWhs in thousands) |   |
|----------------------------------|--------|------------------------------------------|--------|--------|-------------------------------|--------|
|                             |   | 2009                                     |   |   | 2008                          |   |   | Change |   |   | 2009 |   |   | 2008 |   |   | Change |   |
| Residential                      |   | $                                        | 254.3  |   |                          | $      | 254.6 |   |   |   | -- |   |   |   | 1,910 |   |   |   | 2,075 |   |   |   | (8 | %) |
| Commercial                       |   |                                     | 171.0  |   |                          |   | 165.5 |   |   |   | 3 | % |   |   | 1,567 |   |   |   | 1,651 |   |   |   | (5 | %) |
| Industrial                       |   |                                     | 214.6  |   |                          |   | 222.7 |   |   |   | (4 | %) |   |   | 2,755 |   |   |   | 3,203 |   |   |   | (14 | %) |
| Retail subtotal                  |   |                                     | 639.9  |   |                          |   | 642.8 |   |   |   | -- |   |   |   | 6,232 |   |   |   | 6,929 |   |   |   | (10 | %) |
| Sales for resale:                |   |                                     |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Wholesale                        |   |                                     | 44.4   |   |                          |   | 53.1 |   |   |   | (16 | %) |   |   | 767 |   |   |   | 1,010 |   |   |   | (24 | %) |
| Bulk power and other             |   |                                     | 28.4   |   |                          |   | (1.5 | ) |   |   | 1,993 | % |   |   | 601 |   |   |   | 66 |   |   |   | 811 | % |
| Other (includes wheeling)        |   |                                     | 12.6   |   |                          |   | 19.6 |   |   |   | (36 | %) |   |   | 35 |   |   |   | 38 |   |   |   | (8 | %) |
| Total revenues/sales             |   |                                     | 725.3  |   |                          |   | 714.0 |   |   |   | 2 | % |   |   | 7,635 |   |   |   | 8,043 |   |   |   | (5 | %) |
| Electric production fuel expense |   |                                     | 125.9  |   |                          |   | 114.2 |   |   |   | 10 | % |   |   |   |   |   |   |   |   |   |   |   |   |
| Purchased power expense:         |   |                                     |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Energy                           |   |                                     | 125.6  |   |                          |   | 113.3 |   |   |   | 11 | % |   |   |   |   |   |   |   |   |   |   |   |   |
| Capacity                         |   |                                     | 84.8   |   |                          |   | 89.7 |   |   |   | (5 | %) |   |   |   |   |   |   |   |   |   |   |   |   |
| Total electric production fuel   |   |                                     |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| and purchased power expense      |   |                                     | 336.3  |   |                          |   | 317.2 |   |   |   | 6 | % |   |   |   |   |   |   |   |   |   |   |   |   |
| Margins                          |   | $                                        | 389.0  |   |                          | $      | 396.8 |   |   |   | (2 | %) |   |   |   |   |   |   |   |   |   |   |   |   |

----

|                             |   | Revenues and Costs (dollars in millions) |    |   | MWhs Sold (MWhs in thousands) |   |
|----------------------------------|--------|------------------------------------------|---------|--------|-------------------------------|--------|
|                             |   | 2009                                     |    |   | 2008                          |   |   | Change |   |   | 2009 |   |   | 2008 |   |   | Change |   |
| Residential                      |   | $                                        | 661.6   |   |                          | $      | 650.1 |   |   |   | 2 | % |   |   | 5,622 |   |   |   | 5,816 |   |   |   | (3 | %) |
| Commercial                       |   |                                     | 427.7   |   |                          |   | 412.3 |   |   |   | 4 | % |   |   | 4,550 |   |   |   | 4,638 |   |   |   | (2 | %) |
| Industrial                       |   |                                     | 550.4   |   |                          |   | 564.0 |   |   |   | (2 | %) |   |   | 8,199 |   |   |   | 9,395 |   |   |   | (13 | %) |
| Retail subtotal                  |   |                                     | 1,639.7 |   |                          |   | 1,626.4 |   |   |   | 1 | % |   |   | 18,371 |   |   |   | 19,849 |   |   |   | (7 | %) |
| Sales for resale:                |   |                                     |    |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Wholesale                        |   |                                     | 139.5   |   |                          |   | 154.0 |   |   |   | (9 | %) |   |   | 2,488 |   |   |   | 2,834 |   |   |   | (12 | %) |
| Bulk power and other             |   |                                     | 86.5    |   |                          |   | 32.7 |   |   |   | 165 | % |   |   | 1,606 |   |   |   | 658 |   |   |   | 144 | % |
| Other (includes wheeling)        |   |                                     | 35.5    |   |                          |   | 45.3 |   |   |   | (22 | %) |   |   | 116 |   |   |   | 125 |   |   |   | (7 | %) |
| Total revenues/sales             |   |                                     | 1,901.2 |   |                          |   | 1,858.4 |   |   |   | 2 | % |   |   | 22,581 |   |   |   | 23,466 |   |   |   | (4 | %) |
| Electric production fuel expense |   |                                     | 298.6   |   |                          |   | 317.0 |   |   |   | (6 | %) |   |   |   |   |   |   |   |   |   |   |   |   |
| Purchased power expense:         |   |                                     |    |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Energy                           |   |                                     | 396.8   |   |                          |   | 332.8 |   |   |   | 19 | % |   |   |   |   |   |   |   |   |   |   |   |   |
| Capacity                         |   |                                     | 227.5   |   |                          |   | 226.5 |   |   |   | -- |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Total electric production fuel   |   |                                     |    |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| and purchased power expense      |   |                                     | 922.9   |   |                          |   | 876.3 |   |   |   | 5 | % |   |   |   |   |   |   |   |   |   |   |   |   |
| Margins                          |   | $                                        | 978.3   |   |                          | $      | 982.1 |   |   |   | -- |   |   |   |   |   |   |   |   |   |   |   |   |   |

|           |   | 2009   |   |   | 2008   |   |
|----------------|--------|--------|--------|--------|--------|--------|
| IPL            |   | $      | (6     | )      |   | $      | 3 |   |
| WPL            |   |   | 5      |   |   |   | -- |   |
| Alliant Energy |   | $      | (1     | )      |   | $      | 3 |   |

----

|                                                 |   | Three Months |   |   | Nine Months |   |
|------------------------------------------------------|--------|--------------|--------|--------|-------------|--------|
|                                                 |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| Weather impacts on demand compared to normal weather |   | $            | (35    | )      |        | $      | (13 | ) |   | $ | (36 | ) |   | $ | (13 | ) |
| Gains (losses) from weather derivatives (a)          |   |         | --     |   |        |   | 6 |   |   |   | (3 | ) |   |   | 6 |   |
| Net weather impact                                   |   | $            | (35    | )      |        | $      | (7 | ) |   | $ | (39 | ) |   | $ | (7 | ) |

|                     | Three Months |   | Nine Months |
|--------------------------|--------------|--------|-------------|
|                     | Actual       |   |        |   | Actual |   |   |
| CDD (a):                 | 2009         |   | 2008        |   | Normal |   | 2009 |   | 2008 |   | Normal |
| Cedar Rapids, Iowa (IPL) | 224          |   | 425         |   | 541 |   | 406 |   | 576 |   | 767 |
| Madison, Wisconsin (WPL) | 222          |   | 421         |   | 455 |   | 368 |   | 534 |   | 635 |

----

|                                          |   | Three Months |   |   | Nine Months |   |
|-----------------------------------------------|--------|--------------|--------|--------|-------------|--------|
|                                          |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| DAEC PPA (IPL)                                |   | $            | 38     |   |        | $      | 37 |   |   | $ | 108 |   |   | $ | 104 |   |
| Kewaunee PPA (WPL)                            |   |         | 18     |   |        |   | 15 |   |   |   | 55 |   |   |   | 46 |   |
| Riverside PPA (WPL)                           |   |         | 26     |   |        |   | 26 |   |   |   | 51 |   |   |   | 50 |   |
| RockGen PPA (WPL)(expired May 31, 2009)       |   |         | --     |   |        |   | 4 |   |   |   | 7 |   |   |   | 12 |   |
| Flood-related PPA (IPL) - Summer of 2008 only |   |         | --     |   |        |   | 5 |   |   |   | -- |   |   |   | 5 |   |
| Other                                         |   |         | 3      |   |        |   | 3 |   |   |   | 7 |   |   |   | 10 |   |
|                                          |   | $            | 85     |   |        | $      | 90 |   |   | $ | 228 |   |   | $ | 227 |   |

|                 |   | Revenues and Costs (dollars in millions) |   |   | Dths Sold (Dths in thousands) |   |
|----------------------|--------|------------------------------------------|--------|--------|-------------------------------|--------|
|                 |   | 2009                                     |   |   | 2008                          |   |   | Change |   |   | 2009 |   |   | 2008 |   |   | Change |   |
| Residential          |   | $                                        | 18.5   |   |                          | $      | 29.2 |   |   |   | (37 | %) |   |   | 1,477 |   |   |   | 1,645 |   |   |   | (10 | %) |
| Commercial           |   |                                     | 11.5   |   |                          |   | 24.0 |   |   |   | (52 | %) |   |   | 1,701 |   |   |   | 2,004 |   |   |   | (15 | %) |
| Industrial           |   |                                     | 2.9    |   |                          |   | 9.7 |   |   |   | (70 | %) |   |   | 596 |   |   |   | 988 |   |   |   | (40 | %) |
| Retail subtotal      |   |                                     | 32.9   |   |                          |   | 62.9 |   |   |   | (48 | %) |   |   | 3,774 |   |   |   | 4,637 |   |   |   | (19 | %) |
| Interdepartmental    |   |                                     | 0.6    |   |                          |   | 3.6 |   |   |   | (83 | %) |   |   | 121 |   |   |   | 509 |   |   |   | (76 | %) |
| Transportation/other |   |                                     | 5.6    |   |                          |   | 7.0 |   |   |   | (20 | %) |   |   | 11,081 |   |   |   | 13,555 |   |   |   | (18 | %) |
| Total revenues/sales |   |                                     | 39.1   |   |                          |   | 73.5 |   |   |   | (47 | %) |   |   | 14,976 |   |   |   | 18,701 |   |   |   | (20 | %) |
| Cost of gas sold     |   |                                     | 13.9   |   |                          |   | 46.9 |   |   |   | (70 | %) |   |   |   |   |   |   |   |   |   |   |   |   |
| Margins              |   | $                                        | 25.2   |   |                          | $      | 26.6 |   |   |   | (5 | %) |   |   |   |   |   |   |   |   |   |   |   |   |

----

|                 |   | Revenues and Costs (dollars in millions) |   |   | Dths Sold (Dths in thousands) |   |
|----------------------|--------|------------------------------------------|--------|--------|-------------------------------|--------|
|                 |   | 2009                                     |   |   | 2008                          |   |   | Change |   |   | 2009 |   |   | 2008 |   |   | Change |   |
| Residential          |   | $                                        | 208.4  |   |                          | $      | 271.7 |   |   |   | (23 | %) |   |   | 19,031 |   |   |   | 20,731 |   |   |   | (8 | %) |
| Commercial           |   |                                     | 116.5  |   |                          |   | 167.4 |   |   |   | (30 | %) |   |   | 13,222 |   |   |   | 14,926 |   |   |   | (11 | %) |
| Industrial           |   |                                     | 16.5   |   |                          |   | 34.9 |   |   |   | (53 | %) |   |   | 2,457 |   |   |   | 3,464 |   |   |   | (29 | %) |
| Retail subtotal      |   |                                     | 341.4  |   |                          |   | 474.0 |   |   |   | (28 | %) |   |   | 34,710 |   |   |   | 39,121 |   |   |   | (11 | %) |
| Interdepartmental    |   |                                     | 4.5    |   |                          |   | 7.0 |   |   |   | (36 | %) |   |   | 698 |   |   |   | 1,244 |   |   |   | (44 | %) |
| Transportation/other |   |                                     | 15.9   |   |                          |   | 22.1 |   |   |   | (28 | %) |   |   | 38,689 |   |   |   | 44,832 |   |   |   | (14 | %) |
| Total revenues/sales |   |                                     | 361.8  |   |                          |   | 503.1 |   |   |   | (28 | %) |   |   | 74,097 |   |   |   | 85,197 |   |   |   | (13 | %) |
| Cost of gas sold     |   |                                     | 240.5  |   |                          |   | 365.8 |   |   |   | (34 | %) |   |   |   |   |   |   |   |   |   |   |   |   |
| Margins              |   | $                                        | 121.3  |   |                          | $      | 137.3 |   |   |   | (12 | %) |   |   |   |   |   |   |   |   |   |   |   |   |

|                                                 |   | Three Months |   |   | Nine Months |   |
|------------------------------------------------------|--------|--------------|--------|--------|-------------|--------|
|                                                 |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| Weather impacts on demand compared to normal weather |   | $            | (1     | )      |        | $      | -- |   |   | $ | 3 |   |   | $ | 9 |   |
| Losses from weather derivatives (a)                  |   |         | --     |   |        |   | -- |   |   |   | (3 | ) |   |   | (3 | ) |
| Net weather impact                                   |   | $            | (1     | )      |        | $      | -- |   |   | $ | -- |   |   | $ | 6 |   |

|                     | Three Months |   | Nine Months |
|--------------------------|--------------|--------|-------------|
|                     | Actual       |   |        |   | Actual |   |   |
| HDD (a):                 | 2009         |   | 2008        |   | Normal |   | 2009 |   | 2008 |   | Normal |
| Cedar Rapids, Iowa (IPL) | 143          |   | 114         |   | 147 |   | 4,492 |   | 4,858 |   | 4,211 |
| Madison, Wisconsin (WPL) | 170          |   | 107         |   | 187 |   | 4,764 |   | 4,903 |   | 4,524 |

----

|                              |   | Three Months |   |   | Nine Months |   |
|-----------------------------------|--------|--------------|--------|--------|-------------|--------|
|                              |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| RMT (including WindConnect®) |   | $            | 89.9   |   |        | $      | 144.4 |   |   | $ | 212.4 |   |   | $ | 325.1 |   |
| Transportation                    |   |         | 9.0    |   |        |   | 8.9 |   |   |   | 25.9 |   |   |   | 26.6 |   |
| Non-regulated Generation          |   |         | 1.8    |   |        |   | 9.1 |   |   |   | 6.0 |   |   |   | 22.3 |   |
| Other (includes eliminations)     |   |         | 0.5    |   |        |   | (0.4 | ) |   |   | 1.2 |   |   |   | (0.1 | ) |
|                              |   | $            | 101.2  |   |        | $      | 162.0 |   |   | $ | 245.5 |   |   | $ | 373.9 |   |

|                                                                            |   | Alliant |   |   |   |   |   |   |   |
|---------------------------------------------------------------------------------|--------|---------|--------|--------|--------|--------|--------|--------|--------|
|                                                                            |   | Energy  |   |   | IPL    |   |   | WPL    |   |
| Lower steam fuel, operation and maintenance expenses at IPL                     |   | $       | (16    | )      |   | $      | (16    | )      |   | $ | -- |   |
| Incremental expenses incurred in 2008 related to severe flooding in 2008 at IPL |   |    | (5     | )      |   |   | (5     | )      |   |   | -- |   |
| Lower electric generation maintenance expenses at IPL                           |   |    | (3     | )      |   |   | (3     | )      |   |   | -- |   |
| Deferral of retail pension and benefits costs in 2009 at WPL                    |   |    | (3     | )      |   |   | --     |   |   |   | (3 | ) |
| Higher pension and other postretirement benefits costs                          |   |    | 8      |   |   |   | 4      |   |   |   | 4 |   |
| Other (includes impact of cost saving initiatives)                              |   |    | (2     | )      |   |   | 1      |   |   |   | (3 | ) |
|                                                                            |   | $       | (21    | )      |   | $      | (19    | )      |   | $ | (2 | ) |

----

|                                                                            |   | Alliant |   |   |   |   |   |   |   |
|---------------------------------------------------------------------------------|--------|---------|--------|--------|--------|--------|--------|--------|--------|
|                                                                            |   | Energy  |   |   | IPL    |   |   | WPL    |   |
| Lower electric generation maintenance expenses at IPL                           |   | $       | (11    | )      |   | $      | (11    | )      |   | $ | -- |   |
| Incremental expenses incurred in 2008 related to severe flooding in 2008 at IPL |   |    | (11    | )      |   |   | (11    | )      |   |   | -- |   |
| Deferral of retail pension and benefits costs in 2009 at WPL                    |   |    | (10    | )      |   |   | --     |   |   |   | (10 | ) |
| Lower steam fuel, operation and maintenance expenses at IPL                     |   |    | (10    | )      |   |   | (10    | )      |   |   | -- |   |
| Higher pension and other postretirement benefits costs                          |   |    | 24     |   |   |   | 13     |   |   |   | 11 |   |
| Restructuring charges in the second quarter of 2009                             |   |    | 11     |   |   |   | 4      |   |   |   | 7 |   |
| Incremental expenses incurred in 2009 related to severe flooding in 2008 at IPL |   |    | 4      |   |   |   | 4      |   |   |   | -- |   |
| Steam asset impairment in the second quarter of 2009 at IPL                     |   |    | 4      |   |   |   | 4      |   |   |   | -- |   |
| Higher expenses related to coal sales at IPL                                    |   |    | 3      |   |   |   | 3      |   |   |   | -- |   |
| Other (includes impact of cost saving initiatives)                              |   |    | (9     | )      |   |   | (2     | )      |   |   | (7 | ) |
|                                                                            |   | $       | (5     | )      |   | $      | (6     | )      |   | $ | 1 |   |

|                              |   | Three Months |   |   | Nine Months |   |
|-----------------------------------|--------|--------------|--------|--------|-------------|--------|
|                              |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| RMT (including WindConnect®) |   | $            | 88.8   |   |        | $      | 131.0 |   |   | $ | 213.0 |   |   | $ | 298.8 |   |
| Transportation                    |   |         | 3.9    |   |        |   | 4.3 |   |   |   | 12.5 |   |   |   | 14.1 |   |
| Non-regulated Generation          |   |         | 0.7    |   |        |   | 6.2 |   |   |   | 2.4 |   |   |   | 8.4 |   |
| Other (includes eliminations)     |   |         | 2.3    |   |        |   | -- |   |   |   | 2.8 |   |   |   | (2.5 | ) |
|                              |   | $            | 95.7   |   |        | $      | 141.5 |   |   | $ | 230.7 |   |   | $ | 318.8 |   |

----

|                                                                  |   | Alliant |   |   |   |   |   |   |   |
|-----------------------------------------------------------------------|--------|---------|--------|--------|--------|--------|--------|--------|--------|
|                                                                  |   | Energy  |   |   | IPL    |   |   | WPL    |   |
| Interest expense variances from certain issuances of long-term debt:  |   |    |   |   |   |   |   |   |   |
| IPL’s 7.25% senior debentures issued in October 2008            |   | $       | 5      |   |   | $      | 5      |   |   | $ | -- |   |
| WPL’s 7.6% debentures issued in October 2008                    |   |    | 4      |   |   |   | --     |   |   |   | 4 |   |
| IPL’s 6.25% senior debentures issued in July 2009               |   |    | 4      |   |   |   | 4      |   |   |   | -- |   |
| WPL’s 5% debentures issued in July 2009                         |   |    | 3      |   |   |   | --     |   |   |   | 3 |   |
| Interest expense variances from certain reductions in long-term debt: |   |    |   |   |   |   |   |   |   |   |   |   |
| IPL’s 6.625% senior debentures retired in August 2009           |   |    | (2     | )      |   |   | (2     | )      |   |   | -- |   |
| WPL’s 5.7% debentures retired in October 2008                   |   |    | (1     | )      |   |   | --     |   |   |   | (1 | ) |
| Corporate Services 4.55% senior notes retired in October 2008         |   |    | (1     | )      |   |   | --     |   |   |   | -- |   |
| Other (includes impact of lower commercial paper interest rates)      |   |    | --     |   |   |   | (1     | )      |   |   | (1 | ) |
|                                                                  |   | $       | 12     |   |   | $      | 6      |   |   | $ | 5 |   |

|                                                                  |   | Alliant |   |   |   |   |   |   |   |
|-----------------------------------------------------------------------|--------|---------|--------|--------|--------|--------|--------|--------|--------|
|                                                                  |   | Energy  |   |   | IPL    |   |   | WPL    |   |
| Interest expense variances from certain issuances of long-term debt:  |   |    |   |   |   |   |   |   |   |
| WPL’s 7.6% debentures issued in October 2008                    |   | $       | 14     |   |   | $      | --     |   |   | $ | 14 |   |
| IPL’s 7.25% senior debentures issued in October 2008            |   |    | 14     |   |   |   | 14     |   |   |   | -- |   |
| IPL’s 6.25% senior debentures issued in July 2009               |   |    | 4      |   |   |   | 4      |   |   |   | -- |   |
| WPL’s 5% debentures issued in July 2009                         |   |    | 3      |   |   |   | --     |   |   |   | 3 |   |
| Interest expense variances from certain reductions in long-term debt: |   |    |   |   |   |   |   |   |   |   |   |   |
| WPL’s 5.7% debentures retired in October 2008                   |   |    | (3     | )      |   |   | --     |   |   |   | (3 | ) |
| Corporate Services 4.55% senior notes retired in October 2008         |   |    | (3     | )      |   |   | --     |   |   |   | -- |   |
| IPL’s 6.625% senior debentures retired in August 2009           |   |    | (2     | )      |   |   | (2     | )      |   |   | -- |   |
| Other (includes impact of lower commercial paper interest rates)      |   |    | (3     | )      |   |   | (4     | )      |   |   | (4 | ) |
|                                                                  |   | $       | 24     |   |   | $      | 12     |   |   | $ | 10 |   |

----

----

|                             |   | Revenues and Costs (dollars in millions) |   |   | MWhs Sold (MWhs in thousands) |   |
|----------------------------------|--------|------------------------------------------|--------|--------|-------------------------------|--------|
|                             |   | 2009                                     |   |   | 2008                          |   |   | Change |   |   | 2009 |   |   | 2008 |   |   | Change |   |
| Residential                      |   | $                                        | 150.2  |   |                          | $      | 144.6 |   |   |   | 4 | % |   |   | 1,042 |   |   |   | 1,138 |   |   |   | (8 | %) |
| Commercial                       |   |                                     | 109.0  |   |                          |   | 102.8 |   |   |   | 6 | % |   |   | 973 |   |   |   | 1,030 |   |   |   | (6 | %) |
| Industrial                       |   |                                     | 133.5  |   |                          |   | 130.2 |   |   |   | 3 | % |   |   | 1,705 |   |   |   | 1,959 |   |   |   | (13 | %) |
| Retail subtotal                  |   |                                     | 392.7  |   |                          |   | 377.6 |   |   |   | 4 | % |   |   | 3,720 |   |   |   | 4,127 |   |   |   | (10 | %) |
| Sales for resale:                |   |                                     |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Wholesale                        |   |                                     | 6.3    |   |                          |   | 6.4 |   |   |   | (2 | %) |   |   | 105 |   |   |   | 116 |   |   |   | (9 | %) |
| Bulk power and other             |   |                                     | 11.8   |   |                          |   | (0.4 | ) |   |   | 3,050 | % |   |   | 190 |   |   |   | 19 |   |   |   | 900 | % |
| Other (includes wheeling)        |   |                                     | 7.1    |   |                          |   | 11.2 |   |   |   | (37 | %) |   |   | 19 |   |   |   | 21 |   |   |   | (10 | %) |
| Total revenues/sales             |   |                                     | 417.9  |   |                          |   | 394.8 |   |   |   | 6 | % |   |   | 4,034 |   |   |   | 4,283 |   |   |   | (6 | %) |
| Electric production fuel expense |   |                                     | 83.5   |   |                          |   | 70.0 |   |   |   | 19 | % |   |   |   |   |   |   |   |   |   |   |   |   |
| Purchased power expense:         |   |                                     |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Energy                           |   |                                     | 47.5   |   |                          |   | 48.6 |   |   |   | (2 | %) |   |   |   |   |   |   |   |   |   |   |   |   |
| Capacity                         |   |                                     | 38.6   |   |                          |   | 41.8 |   |   |   | (8 | %) |   |   |   |   |   |   |   |   |   |   |   |   |
| Total electric production fuel   |   |                                     |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| and purchased power expense      |   |                                     | 169.6  |   |                          |   | 160.4 |   |   |   | 6 | % |   |   |   |   |   |   |   |   |   |   |   |   |
| Margins                          |   | $                                        | 248.3  |   |                          | $      | 234.4 |   |   |   | 6 | % |   |   |   |   |   |   |   |   |   |   |   |   |

|                             |   | Revenues and Costs (dollars in millions) |    |   | MWhs Sold (MWhs in thousands) |   |
|----------------------------------|--------|------------------------------------------|---------|--------|-------------------------------|--------|
|                             |   | 2009                                     |    |   | 2008                          |   |   | Change |   |   | 2009 |   |   | 2008 |   |   | Change |   |
| Residential                      |   | $                                        | 367.3   |   |                          | $      | 351.2 |   |   |   | 5 | % |   |   | 3,068 |   |   |   | 3,201 |   |   |   | (4 | %) |
| Commercial                       |   |                                     | 259.2   |   |                          |   | 244.0 |   |   |   | 6 | % |   |   | 2,849 |   |   |   | 2,912 |   |   |   | (2 | %) |
| Industrial                       |   |                                     | 323.4   |   |                          |   | 312.3 |   |   |   | 4 | % |   |   | 5,108 |   |   |   | 5,786 |   |   |   | (12 | %) |
| Retail subtotal                  |   |                                     | 949.9   |   |                          |   | 907.5 |   |   |   | 5 | % |   |   | 11,025 |   |   |   | 11,899 |   |   |   | (7 | %) |
| Sales for resale:                |   |                                     |    |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Wholesale                        |   |                                     | 17.7    |   |                          |   | 17.6 |   |   |   | 1 | % |   |   | 303 |   |   |   | 336 |   |   |   | (10 | %) |
| Bulk power and other             |   |                                     | 36.6    |   |                          |   | 22.8 |   |   |   | 61 | % |   |   | 546 |   |   |   | 438 |   |   |   | 25 | % |
| Other (includes wheeling)        |   |                                     | 18.5    |   |                          |   | 25.7 |   |   |   | (28 | %) |   |   | 62 |   |   |   | 69 |   |   |   | (10 | %) |
| Total revenues/sales             |   |                                     | 1,022.7 |   |                          |   | 973.6 |   |   |   | 5 | % |   |   | 11,936 |   |   |   | 12,742 |   |   |   | (6 | %) |
| Electric production fuel expense |   |                                     | 181.8   |   |                          |   | 187.2 |   |   |   | (3 | %) |   |   |   |   |   |   |   |   |   |   |   |   |
| Purchased power expense:         |   |                                     |    |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Energy                           |   |                                     | 165.2   |   |                          |   | 126.8 |   |   |   | 30 | % |   |   |   |   |   |   |   |   |   |   |   |   |
| Capacity                         |   |                                     | 108.6   |   |                          |   | 109.4 |   |   |   | (1 | %) |   |   |   |   |   |   |   |   |   |   |   |   |
| Total electric production fuel   |   |                                     |    |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| and purchased power expense      |   |                                     | 455.6   |   |                          |   | 423.4 |   |   |   | 8 | % |   |   |   |   |   |   |   |   |   |   |   |   |
| Margins                          |   | $                                        | 567.1   |   |                          | $      | 550.2 |   |   |   | 3 | % |   |   |   |   |   |   |   |   |   |   |   |   |

----

|                                                 |   | Three Months |   |   | Nine Months |   |
|------------------------------------------------------|--------|--------------|--------|--------|-------------|--------|
|                                                 |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| Weather impacts on demand compared to normal weather |   | $            | (25    | )      |        | $      | (11 | ) |   | $ | (25 | ) |   | $ | (11 | ) |
| Gains (losses) from weather derivatives (a)          |   |         | --     |   |        |   | 5 |   |   |   | (2 | ) |   |   | 5 |   |
| Net weather impact                                   |   | $            | (25    | )      |        | $      | (6 | ) |   | $ | (27 | ) |   | $ | (6 | ) |

|                 |   | Revenues and Costs (dollars in millions) |   |   | Dths Sold (Dths in thousands) |   |
|----------------------|--------|------------------------------------------|--------|--------|-------------------------------|--------|
|                 |   | 2009                                     |   |   | 2008                          |   |   | Change |   |   | 2009 |   |   | 2008 |   |   | Change |   |
| Residential          |   | $                                        | 10.3   |   |                          | $      | 16.7 |   |   |   | (38 | %) |   |   | 707 |   |   |   | 954 |   |   |   | (26 | %) |
| Commercial           |   |                                     | 6.5    |   |                          |   | 13.6 |   |   |   | (52 | %) |   |   | 782 |   |   |   | 1,172 |   |   |   | (33 | %) |
| Industrial           |   |                                     | 2.5    |   |                          |   | 8.8 |   |   |   | (72 | %) |   |   | 520 |   |   |   | 918 |   |   |   | (43 | %) |
| Retail subtotal      |   |                                     | 19.3   |   |                          |   | 39.1 |   |   |   | (51 | %) |   |   | 2,009 |   |   |   | 3,044 |   |   |   | (34 | %) |
| Interdepartmental    |   |                                     | 0.5    |   |                          |   | 0.8 |   |   |   | (38 | %) |   |   | 117 |   |   |   | 80 |   |   |   | 46 | % |
| Transportation/other |   |                                     | 2.8    |   |                          |   | 2.3 |   |   |   | 22 | % |   |   | 6,598 |   |   |   | 8,101 |   |   |   | (19 | %) |
| Total revenues/sales |   |                                     | 22.6   |   |                          |   | 42.2 |   |   |   | (46 | %) |   |   | 8,724 |   |   |   | 11,225 |   |   |   | (22 | %) |
| Cost of gas sold     |   |                                     | 9.0    |   |                          |   | 28.2 |   |   |   | (68 | %) |   |   |   |   |   |   |   |   |   |   |   |   |
| Margins              |   | $                                        | 13.6   |   |                          | $      | 14.0 |   |   |   | (3 | %) |   |   |   |   |   |   |   |   |   |   |   |   |

----

|                 |   | Revenues and Costs (dollars in millions) |   |   | Dths Sold (Dths in thousands) |   |
|----------------------|--------|------------------------------------------|--------|--------|-------------------------------|--------|
|                 |   | 2009                                     |   |   | 2008                          |   |   | Change |   |   | 2009 |   |   | 2008 |   |   | Change |   |
| Residential          |   | $                                        | 119.0  |   |                          | $      | 157.2 |   |   |   | (24 | %) |   |   | 10,830 |   |   |   | 12,202 |   |   |   | (11 | %) |
| Commercial           |   |                                     | 66.1   |   |                          |   | 97.0 |   |   |   | (32 | %) |   |   | 7,115 |   |   |   | 8,629 |   |   |   | (18 | %) |
| Industrial           |   |                                     | 12.6   |   |                          |   | 27.1 |   |   |   | (54 | %) |   |   | 1,951 |   |   |   | 2,723 |   |   |   | (28 | %) |
| Retail subtotal      |   |                                     | 197.7  |   |                          |   | 281.3 |   |   |   | (30 | %) |   |   | 19,896 |   |   |   | 23,554 |   |   |   | (16 | %) |
| Interdepartmental    |   |                                     | 2.6    |   |                          |   | 2.1 |   |   |   | 24 | % |   |   | 429 |   |   |   | 196 |   |   |   | 119 | % |
| Transportation/other |   |                                     | 7.8    |   |                          |   | 9.5 |   |   |   | (18 | %) |   |   | 22,682 |   |   |   | 26,770 |   |   |   | (15 | %) |
| Total revenues/sales |   |                                     | 208.1  |   |                          |   | 292.9 |   |   |   | (29 | %) |   |   | 43,007 |   |   |   | 50,520 |   |   |   | (15 | %) |
| Cost of gas sold     |   |                                     | 141.2  |   |                          |   | 220.1 |   |   |   | (36 | %) |   |   |   |   |   |   |   |   |   |   |   |   |
| Margins              |   | $                                        | 66.9   |   |                          | $      | 72.8 |   |   |   | (8 | %) |   |   |   |   |   |   |   |   |   |   |   |   |

|                                                 |   | Three Months |   |   | Nine Months |   |
|------------------------------------------------------|--------|--------------|--------|--------|-------------|--------|
|                                                 |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| Weather impacts on demand compared to normal weather |   | $            | --     |   |        | $      | -- |   |   | $ | 2 |   |   | $ | 6 |   |
| Losses from weather derivatives (a)                  |   |         | --     |   |        |   | -- |   |   |   | (2 | ) |   |   | (2 | ) |
| Net weather impact                                   |   | $            | --     |   |        | $      | -- |   |   | $ | -- |   |   | $ | 4 |   |

----

----

|                             |   | Revenues and Costs (dollars in millions) |   |   | MWhs Sold (MWhs in thousands) |   |
|----------------------------------|--------|------------------------------------------|--------|--------|-------------------------------|--------|
|                             |   | 2009                                     |   |   | 2008                          |   |   | Change |   |   | 2009 |   |   | 2008 |   |   | Change |   |
| Residential                      |   | $                                        | 104.1  |   |                          | $      | 110.0 |   |   |   | (5 | %) |   |   | 868 |   |   |   | 937 |   |   |   | (7 | %) |
| Commercial                       |   |                                     | 62.0   |   |                          |   | 62.7 |   |   |   | (1 | %) |   |   | 594 |   |   |   | 621 |   |   |   | (4 | %) |
| Industrial                       |   |                                     | 81.1   |   |                          |   | 92.5 |   |   |   | (12 | %) |   |   | 1,050 |   |   |   | 1,244 |   |   |   | (16 | %) |
| Retail subtotal                  |   |                                     | 247.2  |   |                          |   | 265.2 |   |   |   | (7 | %) |   |   | 2,512 |   |   |   | 2,802 |   |   |   | (10 | %) |
| Sales for resale:                |   |                                     |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Wholesale                        |   |                                     | 38.1   |   |                          |   | 46.7 |   |   |   | (18 | %) |   |   | 662 |   |   |   | 894 |   |   |   | (26 | %) |
| Bulk power and other             |   |                                     | 16.6   |   |                          |   | (1.1 | ) |   |   | 1,609 | % |   |   | 411 |   |   |   | 47 |   |   |   | 774 | % |
| Other                            |   |                                     | 5.5    |   |                          |   | 8.4 |   |   |   | (35 | %) |   |   | 16 |   |   |   | 17 |   |   |   | (6 | %) |
| Total revenues/sales             |   |                                     | 307.4  |   |                          |   | 319.2 |   |   |   | (4 | %) |   |   | 3,601 |   |   |   | 3,760 |   |   |   | (4 | %) |
| Electric production fuel expense |   |                                     | 42.4   |   |                          |   | 44.2 |   |   |   | (4 | %) |   |   |   |   |   |   |   |   |   |   |   |   |
| Purchased power expense:         |   |                                     |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Energy                           |   |                                     | 78.1   |   |                          |   | 64.7 |   |   |   | 21 | % |   |   |   |   |   |   |   |   |   |   |   |   |
| Capacity                         |   |                                     | 46.2   |   |                          |   | 47.9 |   |   |   | (4 | %) |   |   |   |   |   |   |   |   |   |   |   |   |
| Total electric production fuel   |   |                                     |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| and purchased power expense      |   |                                     | 166.7  |   |                          |   | 156.8 |   |   |   | 6 | % |   |   |   |   |   |   |   |   |   |   |   |   |
| Margins                          |   | $                                        | 140.7  |   |                          | $      | 162.4 |   |   |   | (13 | %) |   |   |   |   |   |   |   |   |   |   |   |   |

----

|                             |   | Revenues and Costs (dollars in millions) |   |   | MWhs Sold (MWhs in thousands) |   |
|----------------------------------|--------|------------------------------------------|--------|--------|-------------------------------|--------|
|                             |   | 2009                                     |   |   | 2008                          |   |   | Change |   |   | 2009 |   |   | 2008 |   |   | Change |   |
| Residential                      |   | $                                        | 294.3  |   |                          | $      | 298.9 |   |   |   | (2 | %) |   |   | 2,554 |   |   |   | 2,615 |   |   |   | (2 | %) |
| Commercial                       |   |                                     | 168.5  |   |                          |   | 168.3 |   |   |   | -- |   |   |   | 1,701 |   |   |   | 1,726 |   |   |   | (1 | %) |
| Industrial                       |   |                                     | 227.0  |   |                          |   | 251.7 |   |   |   | (10 | %) |   |   | 3,091 |   |   |   | 3,609 |   |   |   | (14 | %) |
| Retail subtotal                  |   |                                     | 689.8  |   |                          |   | 718.9 |   |   |   | (4 | %) |   |   | 7,346 |   |   |   | 7,950 |   |   |   | (8 | %) |
| Sales for resale:                |   |                                     |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Wholesale                        |   |                                     | 121.8  |   |                          |   | 136.4 |   |   |   | (11 | %) |   |   | 2,185 |   |   |   | 2,498 |   |   |   | (13 | %) |
| Bulk power and other             |   |                                     | 49.9   |   |                          |   | 9.9 |   |   |   | 404 | % |   |   | 1,060 |   |   |   | 220 |   |   |   | 382 | % |
| Other                            |   |                                     | 17.0   |   |                          |   | 19.6 |   |   |   | (13 | %) |   |   | 54 |   |   |   | 56 |   |   |   | (4 | %) |
| Total revenues/sales             |   |                                     | 878.5  |   |                          |   | 884.8 |   |   |   | (1 | %) |   |   | 10,645 |   |   |   | 10,724 |   |   |   | (1 | %) |
| Electric production fuel expense |   |                                     | 116.8  |   |                          |   | 129.8 |   |   |   | (10 | %) |   |   |   |   |   |   |   |   |   |   |   |   |
| Purchased power expense:         |   |                                     |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Energy                           |   |                                     | 231.6  |   |                          |   | 206.0 |   |   |   | 12 | % |   |   |   |   |   |   |   |   |   |   |   |   |
| Capacity                         |   |                                     | 118.9  |   |                          |   | 117.1 |   |   |   | 2 | % |   |   |   |   |   |   |   |   |   |   |   |   |
| Total electric production fuel   |   |                                     |   |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| and purchased power expense      |   |                                     | 467.3  |   |                          |   | 452.9 |   |   |   | 3 | % |   |   |   |   |   |   |   |   |   |   |   |   |
| Margins                          |   | $                                        | 411.2  |   |                          | $      | 431.9 |   |   |   | (5 | %) |   |   |   |   |   |   |   |   |   |   |   |   |

|                                                 |   | Three Months |   |   | Nine Months |   |
|------------------------------------------------------|--------|--------------|--------|--------|-------------|--------|
|                                                 |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| Weather impacts on demand compared to normal weather |   | $            | (10    | )      |        | $      | (2 | ) |   | $ | (11 | ) |   | $ | (2 | ) |
| Gains (losses) from weather derivatives (a)          |   |         | --     |   |        |   | 1 |   |   |   | (1 | ) |   |   | 1 |   |
| Net weather impact                                   |   | $            | (10    | )      |        | $      | (1 | ) |   | $ | (12 | ) |   | $ | (1 | ) |

----

|                 |   | Revenues and Costs (dollars in millions) |   |   | Dths Sold (Dths in thousands) |   |
|----------------------|--------|------------------------------------------|--------|--------|-------------------------------|--------|
|                 |   | 2009                                     |   |   | 2008                          |   |   | Change |   |   | 2009 |   |   | 2008 |   |   | Change |   |
| Residential          |   | $                                        | 8.2    |   |                          | $      | 12.5 |   |   |   | (34 | %) |   |   | 770 |   |   |   | 691 |   |   |   | 11 | % |
| Commercial           |   |                                     | 5.0    |   |                          |   | 10.4 |   |   |   | (52 | %) |   |   | 919 |   |   |   | 832 |   |   |   | 10 | % |
| Industrial           |   |                                     | 0.4    |   |                          |   | 0.9 |   |   |   | (56 | %) |   |   | 76 |   |   |   | 70 |   |   |   | 9 | % |
| Retail subtotal      |   |                                     | 13.6   |   |                          |   | 23.8 |   |   |   | (43 | %) |   |   | 1,765 |   |   |   | 1,593 |   |   |   | 11 | % |
| Interdepartmental    |   |                                     | 0.1    |   |                          |   | 2.8 |   |   |   | (96 | %) |   |   | 4 |   |   |   | 429 |   |   |   | (99 | %) |
| Transportation/other |   |                                     | 2.8    |   |                          |   | 4.7 |   |   |   | (40 | %) |   |   | 4,483 |   |   |   | 5,454 |   |   |   | (18 | %) |
| Total revenues/sales |   |                                     | 16.5   |   |                          |   | 31.3 |   |   |   | (47 | %) |   |   | 6,252 |   |   |   | 7,476 |   |   |   | (16 | %) |
| Cost of gas sold     |   |                                     | 4.9    |   |                          |   | 18.7 |   |   |   | (74 | %) |   |   |   |   |   |   |   |   |   |   |   |   |
| Margins              |   | $                                        | 11.6   |   |                          | $      | 12.6 |   |   |   | (8 | %) |   |   |   |   |   |   |   |   |   |   |   |   |

|                 |   | Revenues and Costs (dollars in millions) |   |   | Dths Sold (Dths in thousands) |   |
|----------------------|--------|------------------------------------------|--------|--------|-------------------------------|--------|
|                 |   | 2009                                     |   |   | 2008                          |   |   | Change |   |   | 2009 |   |   | 2008 |   |   | Change |   |
| Residential          |   | $                                        | 89.4   |   |                          | $      | 114.5 |   |   |   | (22 | %) |   |   | 8,201 |   |   |   | 8,529 |   |   |   | (4 | %) |
| Commercial           |   |                                     | 50.4   |   |                          |   | 70.4 |   |   |   | (28 | %) |   |   | 6,107 |   |   |   | 6,297 |   |   |   | (3 | %) |
| Industrial           |   |                                     | 3.9    |   |                          |   | 7.8 |   |   |   | (50 | %) |   |   | 506 |   |   |   | 741 |   |   |   | (32 | %) |
| Retail subtotal      |   |                                     | 143.7  |   |                          |   | 192.7 |   |   |   | (25 | %) |   |   | 14,814 |   |   |   | 15,567 |   |   |   | (5 | %) |
| Interdepartmental    |   |                                     | 1.9    |   |                          |   | 4.9 |   |   |   | (61 | %) |   |   | 269 |   |   |   | 1,048 |   |   |   | (74 | %) |
| Transportation/other |   |                                     | 8.1    |   |                          |   | 12.6 |   |   |   | (36 | %) |   |   | 16,007 |   |   |   | 18,062 |   |   |   | (11 | %) |
| Total revenues/sales |   |                                     | 153.7  |   |                          |   | 210.2 |   |   |   | (27 | %) |   |   | 31,090 |   |   |   | 34,677 |   |   |   | (10 | %) |
| Cost of gas sold     |   |                                     | 99.3   |   |                          |   | 145.7 |   |   |   | (32 | %) |   |   |   |   |   |   |   |   |   |   |   |   |
| Margins              |   | $                                        | 54.4   |   |                          | $      | 64.5 |   |   |   | (16 | %) |   |   |   |   |   |   |   |   |   |   |   |   |

|                                                 |   | Three Months |   |   | Nine Months |   |
|------------------------------------------------------|--------|--------------|--------|--------|-------------|--------|
|                                                 |   | 2009         |   |   | 2008        |   |   | 2009 |   |   | 2008 |   |
| Weather impacts on demand compared to normal weather |   | $            | (1     | )      |        | $      | -- |   |   | $ | 1 |   |   | $ | 3 |   |
| Losses from weather derivatives (a)                  |   |         | --     |   |        |   | -- |   |   |   | (1 | ) |   |   | (1 | ) |
| Net weather impact                                   |   | $            | (1     | )      |        | $      | -- |   |   | $ | -- |   |   | $ | 2 |   |

----

----

|                                      |   | Alliant Energy |    |   |   |   |   |   |   |
|-------------------------------------------|--------|----------------|---------|--------|--------|--------|--------|--------|--------|
|                                      |   | (Consolidated) |    |   | IPL    |   |   | WPL    |   |
| Common equity                             |   | $              | 2,759.7 |   |   |   | 50.8   | %      |   | $ | 1,341.7 |   |   |   | 50.0 | % |   | $ | 1,252.7 |   |   |   | 53.4 | % |
| Preferred equity                          |   |           | 243.8   |   |   |   | 4.5    | %      |   |   | 183.8 |   |   |   | 6.8 | % |   |   | 60.0 |   |   |   | 2.6 | % |
| Noncontrolling interest                   |   |           | 2.1     |   |   |   | --     | %      |   |   | -- |   |   |   | -- | % |   |   | -- |   |   |   | -- | % |
| Long-term debt (incl. current maturities) |   |           | 2,257.4 |   |   |   | 41.6   | %      |   |   | 1,158.6 |   |   |   | 43.2 | % |   |   | 1,031.5 |   |   |   | 44.0 | % |
| Short-term debt                           |   |           | 170.0   |   |   |   | 3.1    | %      |   |   | -- |   |   |   | -- | % |   |   | -- |   |   |   | -- | % |
|                                      |   | $              | 5,433.0 |   |   |   | 100.0  | %      |   | $ | 2,684.1 |   |   |   | 100.0 | % |   | $ | 2,344.2 |   |   |   | 100.0 | % |

|                                 |   | Alliant Energy |   |   | IPL    |   |   | WPL    |   |
|--------------------------------------|--------|----------------|--------|--------|--------|--------|--------|--------|--------|
|                                 |   | 2009           |   |   | 2008   |   |   | 2009   |   |   | 2008 |   |   | 2009 |   |   | 2008 |   |
| Cash and cash equivalents at Jan. 1  |   | $              | 346.9  |   |   | $      | 745.6  |   |   | $ | 6.2 |   |   | $ | 39.4 |   |   | $ | 4.5 |   |   | $ | 0.4 |   |
| Cash flows from (used for):          |   |           |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Operating activities                 |   |           | 590.5  |   |   |   | 415.3  |   |   |   | 350.0 |   |   |   | 159.2 |   |   |   | 256.1 |   |   |   | 212.3 |   |
| Investing activities                 |   |           | (883.2 | )      |   |   | (608.7 | )      |   |   | (547.5 | ) |   |   | (349.0 | ) |   |   | (396.7 | ) |   |   | (247.7 | ) |
| Financing activities                 |   |           | 122.5  |   |   |   | (172.8 | )      |   |   | 196.4 |   |   |   | 151.1 |   |   |   | 226.8 |   |   |   | 36.7 |   |
| Net increase (decrease)              |   |           | (170.2 | )      |   |   | (366.2 | )      |   |   | (1.1 | ) |   |   | (38.7 | ) |   |   | 86.2 |   |   |   | 1.3 |   |
| Cash and cash equivalents at Sep. 30 |   | $              | 176.7  |   |   | $      | 379.4  |   |   | $ | 5.1 |   |   | $ | 0.7 |   |   | $ | 90.7 |   |   | $ | 1.7 |   |

----

|                                 |   | Alliant Energy |   |   | IPL    |   |   | WPL    |   |
|--------------------------------------|--------|----------------|--------|--------|--------|--------|--------|--------|--------|
| Utility business (a):                |   | 2009           |   |   | 2010   |   |   | 2011   |   |   | 2009 |   |   | 2010 |   |   | 2011 |   |   | 2009 |   |   | 2010 |   |   | 2011 |   |
| Generation - new facilities:         |   |           |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| IPL wind - Whispering Willow - East  |   | $              | 290    |   |   | $      | 10     |   |   | $ | -- |   |   | $ | 290 |   |   | $ | 10 |   |   | $ | -- |   |   | $ | -- |   |   | $ | -- |   |   | $ | -- |   |
| IPL wind - Whispering Willow - West  |   |           | 25     |   |   |   | 90     |   |   |   | 140 |   |   |   | 25 |   |   |   | 90 |   |   |   | 140 |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |
| WPL wind - Bent Tree                 |   |           | 205    |   |   |   | 260    |   |   |   | 10 |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | 205 |   |   |   | 260 |   |   |   | 10 |   |
| WPL gas - Neenah Energy Facility (b) |   |           | --     |   |   |   | --     |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | -- |   |   |   | 92 |   |   |   | -- |   |   |   | -- |   |
| Total generation - new facilities    |   |           | 520    |   |   |   | 360    |   |   |   | 150 |   |   |   | 315 |   |   |   | 100 |   |   |   | 140 |   |   |   | 297 |   |   |   | 260 |   |   |   | 10 |   |
| Environmental                        |   |           | 130    |   |   |   | 110    |   |   |   | 225 |   |   |   | 115 |   |   |   | 50 |   |   |   | 25 |   |   |   | 15 |   |   |   | 60 |   |   |   | 200 |   |
| AMI                                  |   |           | 70     |   |   |   | 20     |   |   |   | 40 |   |   |   | -- |   |   |   | 15 |   |   |   | 40 |   |   |   | 70 |   |   |   | 5 |   |   |   | -- |   |
| Other utility capital expenditures   |   |           | 475    |   |   |   | 425    |   |   |   | 380 |   |   |   | 305 |   |   |   | 235 |   |   |   | 205 |   |   |   | 170 |   |   |   | 190 |   |   |   | 175 |   |
| Total utility business               |   |           | 1,195  |   |   |   | 915    |   |   |   | 795 |   |   | $ | 735 |   |   | $ | 400 |   |   | $ | 410 |   |   | $ | 552 |   |   | $ | 515 |   |   | $ | 385 |   |
| Non-regulated businesses             |   |           | 15     |   |   |   | 10     |   |   |   | 10 |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                 |   | $              | 1,210  |   |   | $      | 925    |   |   | $ | 805 |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |

----

| (a)   | Cost estimates represent IPL’s or WPL’s estimated portion of total escalated construction and acquisition expenditures in millions of dollars and exclude AFUDC, if applicable. |
|-----------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| (b)   | Refer to Note 1(d) of Alliant Energy’s “Notes to Condensed Consolidated Financial Statements” for discussion of WPL’s acquisition of the Neenah Energy Facility and related assets from Resources on June 1, 2009. |
|-----------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

|           | Requirement   |   | Status at Sep. 30, 2009 |
|----------------|---------------|--------|-------------------------|
| Alliant Energy | Less than 65% |   | 44%                     |
| IPL            | Less than 58% |   | 43%                     |
| WPL            | Less than 58% |   | 47%                     |

----

----

----

----

----

----

----

----

|              |   |          |   |   |          |   |   |                |   |   | Maximum Number (or    |   |
|-------------------|--------|---------------|--------|--------|---------------|--------|--------|---------------------|--------|--------|-----------------------|--------|
|              |   |          |   |   |          |   |   | Total Number of     |   |   | Approximate Dollar    |   |
|              |   | Total Number  |   |   | Average Price |   |   | Shares Purchased as |   |   | Value) of Shares That |   |
|              |   | of Shares     |   |   | Paid Per      |   |   | Part of Publicly    |   |   | May Yet Be Purchased  |   |
| Period            |   | Purchased (a) |   |   | Share         |   |   | Announced Plan      |   |   | Under the Plan (a)    |   |
| July 1 to July 31 |   |          | 9,178  |   |          | $      | 25.31  |                |   |   | --                    |   |   |   | N/A |   |
| Aug. 1 to Aug. 31 |   |          | 4,462  |   |          |   | 26.41  |                |   |   | --                    |   |   |   | N/A |   |
| Sep. 1 to Sep. 30 |   |          | 182    |   |          |   | 27.08  |                |   |   | --                    |   |   |   | N/A |   |
|              |   |          | 13,822 |   |          |   | 25.69  |                |   |   | --                    |   |   |   |   |   |

| (a)   | Includes 182, 3,848 and 182 shares of Alliant Energy common stock for July 1 to July 31, Aug. 1 to Aug. 31, and Sep. 1 to Sep. 30, respectively, purchased on the open market and held in a rabbi trust under the Alliant Energy Deferred Compensation Plan (DCP).  There is no limit on the number of shares of Alliant Energy common stock that may beheld under the DCP, which currently does not have an expiration date.  Also includes 8,996 and 614 shares of Alliant Energy common stock for July 1 to July 31 and Aug. 1 to Aug. 31, respectively, transferred from employees to Alliant Energy to satisfy tax withholding requirements in connection with the vesting of certain restricted stock under the EIP. |
|-----------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | 4.1 | Sixth Supplemental Indenture, dated Sep. 28, 2009, to the Indenture, dated as of Nov. 4, 1999, between Alliant Energy and U.S. Bank National Association (N.A.), as  Trustee (incorporated by reference to Exhibit 4.1 to Alliant Energy’s Form 8-K, dated Sep. 28, 2009 (File No. 1-9894)) |
|--------|-----|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | 4.2 | Second Amended and Restated Five Year Credit Agreement, dated Nov. 7, 2006, among Alliant Energy and the Banks set forth therein (incorporated by reference to Exhibit 4.4 to Alliant Energy’s Registration Statement on Form S-3 (Reg. No. 333-162214)) |
|--------|-----|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | 4.3 | Credit Agreement, dated Sep. 16, 2009, among Alliant Energy, Citibank, N.A. and JPMorgan Chase Bank, N.A. (incorporated by reference to Exhibit 4.6 to Alliant Energy’s Registration Statement on Form S-3 (Reg. No. 333-162214)) |
|--------|-----|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | 4.4 | Second Amended and Restated Five Year Credit Agreement, dated Nov. 7, 2006, among WPL and the Banks set forth therein (incorporated by reference to Exhibit 4.8 to Alliant Energy’s Registration Statement on Form S-3 (Reg. No. 333-162214)) |
|--------|-----|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | 4.5 | Second Amended and Restated Five Year Credit Agreement, dated Nov. 7, 2006, among IPL and the Banks set forth therein (incorporated by reference to Exhibit 4.16 to Alliant Energy’s Registration Statement on Form S-3 (Reg. No. 333-162214)) |
|--------|-----|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | 4.6 | Senior Note Indenture, dated as of Sep. 30, 2009, between Alliant Energy and Wells Fargo Bank, N.A. (incorporated by reference to Exhibit 4.28 to Alliant Energy’s Registration Statement on Form S-3 (Reg. No. 333-162214)) |
|--------|-----|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | 4.7 | Officer’s Certificate, dated Sep. 30, 2009, creating the 4.00% Senior Notes due Oct. 15, 2014 of Alliant Energy (incorporated by reference to Exhibit 4.2 to Alliant Energy’s Form 8-K, dated Sep. 30, 2009 (File No. 1-9894)) |
|--------|-----|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | 12.1 | Ratio of Earnings to Fixed Charges for Alliant Energy |
|--------|------|-------------------------------------------------------|

|   | 12.2 | Ratio of Earnings to Fixed Charges and Ratio of Earnings to Combined Fixed Charges and Preferred Dividend Requirements for IPL |
|--------|------|--------------------------------------------------------------------------------------------------------------------------------|

|   | 12.3 | Ratio of Earnings to Fixed Charges and Ratio of Earnings to Combined Fixed Charges and Preferred Dividend Requirements for WPL |
|--------|------|--------------------------------------------------------------------------------------------------------------------------------|

|   | 31.1 | Certification of the Chairman, President and CEO for Alliant Energy |
|--------|------|---------------------------------------------------------------------|

|   | 31.2 | Certification of the Vice President-CFO and Treasurer for Alliant Energy |
|--------|------|--------------------------------------------------------------------------|

|   | 31.3 | Certification of the Chairman and CEO for IPL |
|--------|------|-----------------------------------------------|

----

|   | 31.4 | Certification of the Vice President-CFO and Treasurer for IPL |
|--------|------|---------------------------------------------------------------|

|   | 31.5 | Certification of the Chairman and CEO for WPL |
|--------|------|-----------------------------------------------|

|   | 31.6 | Certification of the Vice President-CFO and Treasurer for WPL |
|--------|------|---------------------------------------------------------------|

|   | 32.1 | Written Statement of the CEO and CFO Pursuant to 18 U.S.C.§1350 for Alliant Energy |
|--------|------|-----------------------------------------------------------------------------------------|

|   | 32.2 | Written Statement of the CEO and CFO Pursuant to 18 U.S.C.§1350 for IPL |
|--------|------|------------------------------------------------------------------------------|

|   | 32.3 | Written Statement of the CEO and CFO Pursuant to 18 U.S.C.§1350 for WPL |
|--------|------|------------------------------------------------------------------------------|

----

|   | 12.1 | Ratio of Earnings to Fixed Charges for Alliant Energy |
|--------|------|-------------------------------------------------------|

|   | 12.2 | Ratio of Earnings to Fixed Charges and Ratio of Earnings to Combined Fixed Charges and Preferred Dividend Requirements for IPL |
|--------|------|--------------------------------------------------------------------------------------------------------------------------------|

|   | 12.3 | Ratio of Earnings to Fixed Charges and Ratio of Earnings to Combined Fixed Charges and Preferred Dividend Requirements for WPL |
|--------|------|--------------------------------------------------------------------------------------------------------------------------------|

|   | 31.1 | Certification of the Chairman, President and CEO for Alliant Energy |
|--------|------|---------------------------------------------------------------------|

|   | 31.2 | Certification of the Vice President-CFO and Treasurer for Alliant Energy |
|--------|------|--------------------------------------------------------------------------|

|   | 31.3 | Certification of the Chairman and CEO for IPL |
|--------|------|-----------------------------------------------|

|   | 31.4 | Certification of the Vice President-CFO and Treasurer for IPL |
|--------|------|---------------------------------------------------------------|

|   | 31.5 | Certification of the Chairman and CEO for WPL |
|--------|------|-----------------------------------------------|

|   | 31.6 | Certification of the Vice President-CFO and Treasurer for WPL |
|--------|------|---------------------------------------------------------------|

|   | 32.1 | Written Statement of the CEO and CFO Pursuant to 18 U.S.C.§1350 for Alliant Energy |
|--------|------|-----------------------------------------------------------------------------------------|

|   | 32.2 | Written Statement of the CEO and CFO Pursuant to 18 U.S.C.§1350 for IPL |
|--------|------|------------------------------------------------------------------------------|

|   | 32.3 | Written Statement of the CEO and CFO Pursuant to 18 U.S.C.§1350 for WPL |
|--------|------|------------------------------------------------------------------------------|

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