UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 10-Q/A
                               AMENDMENT NO. 1 TO

[X]    QUARTERLY  REPORT  PURSUANT  TO  SECTION  13 OR 15 (d) OF THE  SECURITIES
       EXCHANGE ACT OF 1934
       For the quarterly period ended March 31, 1999

                                       or

[ ]    TRANSITION  REPORT  PURSUANT  TO SECTION  13 OR 15 (d) OF THE  SECURITIES
       EXCHANGE ACT OF 1934
       For the transition period from ______ to _______

               Name of Registrant, State of
Commission     Incorporation, Address of Principal              IRS Employer
File Number    Executive Offices and Telephone Number      Identification Number
-----------    --------------------------------------      ---------------------
1-9894         ALLIANT ENERGY CORPORATION                       39-1380265
               (a Wisconsin corporation)
               222 West Washington Avenue
               Madison, Wisconsin  53703
               Telephone (608)252-3311

0-4117-1       IES UTILITIES INC.                               42-0331370
               (an Iowa corporation)
               Alliant Tower
               Cedar Rapids, Iowa  52401
               Telephone (319)398-4411

0-337          WISCONSIN POWER AND LIGHT COMPANY                39-0714890
               (a Wisconsin corporation)
               222 West Washington Avenue
               Madison, Wisconsin  53703
               Telephone (608)252-3311

               Interstate Energy Corporation
               (Former name of Alliant Energy Corporation)

Indicate  by check mark  whether  the  registrants  (1) have  filed all  reports
required to be filed by Section 13 or 15(d) of the  Securities  Exchange  Act of
1934  during  the  preceding  12 months  (or for such  shorter  period  that the
registrants  were required to file such  reports),  and (2) have been subject to
such filing requirements for the past (90) days. Yes X No _____

This combined Form 10-Q/A is separately filed by Alliant Energy Corporation, IES
Utilities  Inc. and Wisconsin  Power and Light  Company.  Information  contained
herein relating to any individual  registrant is filed by such registrant on its
own behalf.  Each registrant makes no representation as to information  relating
to the other registrants.

Number of shares outstanding of each class of common stock as of April 30, 1999:


Alliant Energy Corporation          Common  stock,  $.01 par  value,  78,116,598
                                    shares outstanding

IES Utilities Inc.                  Common  stock,  $2.50 par value,  13,370,788
                                    shares  outstanding  (all of which are owned
                                    beneficially  and of  record  by  Interstate
                                    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  Interstate
                                    Energy Corporation)

<PAGE>


The  undersigned  registrants  hereby amend Item 1 of their  combined  Quarterly
Report on Form 10-Q for the three  months ended March 31, 1999 to provide in its
entirety as follows:


                                       2
<PAGE>

                                   DEFINITIONS

Certain  abbreviations  or acronyms  used in the text and notes of this combined
Form 10-Q/A are defined below:

Abbreviation or Acronym     Definition
-----------------------     ----------
Corporate Services          Alliant Energy Corporate Services, Inc.
IEC                         Interstate Energy Corporation
IESU                        IES Utilities Inc.
IPC                         Interstate Power Company
McLeod                      McLeodUSA Incorporated
Resources                   Alliant Energy Resources, Inc.
SEC                         Securities and Exchange Commission
WP&L                        Wisconsin Power and Light Company



                                       3
<PAGE>

                          PART I. FINANCIAL INFORMATION

ITEM 1.  CONSOLIDATED FINANCIAL STATEMENTS


                          INTERSTATE ENERGY CORPORATION
                  CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)


                                           For the Three Months Ended March 31
                                               1999                    1998
--------------------------------------------------------------------------------
                                         (in thousands, except per share amounts
Operating revenues:
  Electric utility                          $ 351,338               $ 357,751
  Gas utility                                 133,684                 130,046
  Nonregulated and other                       61,833                  68,486
                                            ---------               ---------
                                              546,855                 556,283
                                            ---------               ---------
--------------------------------------------------------------------------------
Operating expenses:
  Electric and steam production fuels          65,404                  69,556
  Purchased power                              52,065                  56,147
  Cost of utility gas sold                     81,343                  77,280
  Other operation                             130,365                 157,352
  Maintenance                                  23,812                  25,259
  Depreciation and amortization                73,640                  69,832
  Taxes other than income taxes                27,239                  26,977
                                            ---------               ---------
                                              453,868                 482,403
                                            ---------               ---------
--------------------------------------------------------------------------------

Operating income                               92,987                  73,880
                                            ---------               ---------
--------------------------------------------------------------------------------
Interest expense and other:
  Interest expense                             33,400                  30,924
  Allowance for funds used during
    construction                               (1,934)                 (1,503)
  Preferred dividend requirements
    of subsidiaries                             1,676                   1,674
  Miscellaneous, net                           (6,771)                 (3,877)
                                            ---------               ---------
                                               26,371                  27,218
                                            ---------               ---------
--------------------------------------------------------------------------------
Income before income taxes                     66,616                  46,662
                                            ---------               ---------
--------------------------------------------------------------------------------

Income taxes                                   24,872                  17,787
                                            ---------               ---------
--------------------------------------------------------------------------------

Net income                                  $  41,744               $  28,875
                                            =========               =========
--------------------------------------------------------------------------------

Average number of common shares
 outstanding                                   77,780                  76,579
                                            =========               =========
--------------------------------------------------------------------------------

Earnings per average common share
 (basic and diluted)                        $    0.54               $    0.38
                                            =========               =========
--------------------------------------------------------------------------------

The accompanying Notes to Consolidated Financial Statements are an integral part
of these statements.

                                       4
<PAGE>

                          INTERSTATE ENERGY CORPORATION
                           CONSOLIDATED BALANCE SHEETS

                                                March 31,
                                                   1999            December 31,
ASSETS                                         (Unaudited)             1998
--------------------------------------------------------------------------------
                                                        (in thousands)
Property, plant and equipment:
  Utility -
    Plant in service -
      Electric                                $ 4,884,916         $ 4,866,152
      Gas                                         517,775             515,074
      Other                                       409,844             409,711
                                              ------------   -----------------
                                                5,812,535           5,790,937
    Less - Accumulated depreciation             2,917,085           2,852,605
                                              ------------   -----------------
                                                2,895,450           2,938,332
    Construction work in progress                 133,054             119,032
    Nuclear fuel, net of amortization              40,709              44,316
                                              ------------   -----------------
                                                3,069,213           3,101,680
  Other property, plant and equipment,
    net of accumulated depreciation and
    amortization of $189,289 and
    $178,248, respectively                        354,075             355,100
                                              ------------   -----------------
                                                3,423,288           3,456,780
                                              ------------   -----------------
------------------------------------------------------------------------------
Current assets:
  Cash and temporary cash investments              54,183              31,827
  Accounts receivable:
    Customer, less allowance for doubtfu
      accounts of $2,594 and $2,518,
      respectively                                 96,973             102,966
    Other, less allowance for doubtful
      accounts of $499 and $490, respectively      22,273              26,054
  Notes receivable, less allowance for
    doubtful accounts of $117 and $120,
    respectively                                    9,433              13,392
  Production fuel, at average cost                 44,397              54,140
  Materials and supplies, at average cost          55,025              53,490
  Gas stored underground, at average cost          12,489              26,013
  Regulatory assets                                26,628              30,796
  Prepaid gross receipts tax                       16,882              22,222
  Other                                            24,316              30,767
                                              ------------   -----------------
                                                  362,599             391,667
                                              ------------   -----------------
------------------------------------------------------------------------------
Investments:
  Investment in McLeodUSA Inc.                    431,255             320,280
  Nuclear decommissioning trust funds             245,024             225,803
  Investment in foreign entities                  119,124              68,882
  Other                                            52,619              54,776
                                              ------------   -----------------
                                                  848,022             669,741
                                              ------------   -----------------
------------------------------------------------------------------------------
Other assets:
  Regulatory assets                               278,147             284,467
  Deferred charges and other                      159,066             156,682
                                              ------------   -----------------
                                                  437,213             441,149
                                              ------------   -----------------
------------------------------------------------------------------------------
Total assets                                  $ 5,071,122         $ 4,959,337
                                              ============   =================
------------------------------------------------------------------------------

The accompanying Notes to Consolidated Financial Statements are an integral part
of these statements.


                                       5
<PAGE>


                          INTERSTATE ENERGY CORPORATION
                     CONSOLIDATED BALANCE SHEETS (CONTINUED)
<TABLE>
<CAPTION>

                                                                                     March 31,
                                                                                        1999             December 31,
CAPITALIZATION AND LIABILITIES                                                      (Unaudited)              1998
------------------------------------------------------------------------------------------------------------------------
                                                                                  (in thousands, except share amounts)
<S>                                                                                <C>                  <C>
Capitalization:
  Common stock - $.01 par value - authorized 200,000,000 shares;
    outstanding 77,935,693 and 77,630,043 shares, respectively                     $           779      $           776
  Additional paid-in capital                                                               913,728              905,130
  Retained earnings                                                                        540,282              537,372
  Accumulated other comprehensive income                                                   237,434              163,017
                                                                                  -----------------    -----------------
    Total common equity                                                                  1,692,223            1,606,295
                                                                                  -----------------    -----------------

  Cumulative preferred stock of subsidiaries:
   Par/Stated       Authorized        Shares                         Mandatory
      Value           Shares        Outstanding       Series        Redemption
      -----           ------        -----------       ------        ----------
      $ 100              *            449,765      4.40% - 6.20%        No                  44,977               44,977
      $  25              *            599,460          6.50%            No                  14,986               14,986
      $  50           466,406         366,406      4.30% - 6.10%        No                  18,320               18,320
      $  50             **            216,381      4.36% - 7.76%        No                  10,819               10,819
      $  50             **            545,000          6.40%           Yes ***              27,250               27,250
                                                                                  -----------------    -----------------
                                                                                           116,352              116,352
    Less:  unamortized expenses                                                             (2,819)              (2,854)
                                                                                  -----------------    -----------------
      Total cumulative preferred stock of subsidiaries                                     113,533              113,498
                                                                                  -----------------    -----------------

  Long-term debt (excluding current portion)                                             1,545,251            1,543,131
                                                                                  -----------------    -----------------
                                                                                         3,351,007            3,262,924
                                                                                  -----------------    -----------------
* 3,750,000  authorized  shares in total  between  the two classes
**  2,000,000 authorized  shares  in  total  between  the two  classes
***  $53.20  mandatory redemption price
------------------------------------------------------------------------------------------------------------------------
Current liabilities:
  Current maturities and sinking funds                                                      54,084               63,414
  Variable rate demand bonds                                                                56,975               56,975
  Commercial paper                                                                          64,000               64,500
  Notes payable                                                                             50,027               51,784
  Capital lease obligations                                                                 12,146               11,978
  Accounts payable                                                                         163,589              204,297
  Accrued taxes                                                                            106,845               84,921
  Other                                                                                    113,414              111,685
                                                                                  -----------------    -----------------
                                                                                           621,080              649,554
                                                                                  -----------------    -----------------
------------------------------------------------------------------------------------------------------------------------
Other long-term liabilities and deferred credits:
  Accumulated deferred income taxes                                                        738,168              691,624
  Accumulated deferred investment tax credits                                               75,949               77,313
  Environmental liabilities                                                                 68,192               68,399
  Customer advances                                                                         35,964               37,171
  Capital lease obligations                                                                 11,499               13,755
  Other                                                                                    169,263              158,597
                                                                                  -----------------    -----------------
                                                                                         1,099,035            1,046,859
                                                                                  -----------------    -----------------
------------------------------------------------------------------------------------------------------------------------
Total capitalization and liabilities                                                   $ 5,071,122          $ 4,959,337
                                                                                  =================    =================
------------------------------------------------------------------------------------------------------------------------

The accompanying Notes to Consolidated Financial Statements are an integral part
of these statements.

</TABLE>

                                       6

<PAGE>

                          INTERSTATE ENERGY CORPORATION
                CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
<TABLE>
<CAPTION>

                                                                 For the Three Months Ended March 31,
                                                                       1999                1998
-----------------------------------------------------------------------------------------------------
                                                                           (in thousands)
<S>                                                                     <C>                 <C>
Cash flows from operating activities:
  Net income                                                            $ 41,744            $ 28,875
  Adjustments to reconcile net income to net cash flows
   from  operating activities:
    Depreciation and amortization                                         73,640              69,832
    Amortization of nuclear fuel                                           5,024               5,437
    Amortization of deferred energy efficiency expenditures                7,930               8,240
    Deferred taxes and investment tax credits                             (1,799)            (13,424)
    Refueling outage provision                                             2,415               1,299
    Impairment of oil and gas properties                                       -               6,746
    Other                                                                 (2,070)              1,197
  Other changes in assets and liabilities:
    Accounts receivable                                                    9,774              20,221
    Notes receivable                                                       3,959               2,091
    Production fuel                                                        9,743               7,289
    Materials and supplies                                                (1,535)             (1,543)
    Gas stored underground                                                13,524              21,544
    Prepaid gross receipts tax                                             5,340               4,912
    Accounts payable                                                     (40,708)            (23,964)
    Accrued taxes                                                         21,924              29,699
    Adjustment clause balances                                             9,168              14,220
    Benefit obligations and other                                         12,079                (398)
                                                                -----------------   -----------------
       Net cash flows from operating activities                          170,152             182,273
                                                                -----------------   -----------------
-----------------------------------------------------------------------------------------------------
Cash flows used for financing activities:
    Common stock dividends declared                                      (38,834)            (36,580)
    Proceeds from issuance of common stock                                 8,538               2,828
    Net change in Alliant Energy Resources, Inc. credit facility          42,995              29,562
    Proceeds from issuance of other long-term debt                        11,994                  41
    Reductions in other long-term debt                                   (62,310)             (1,013)
    Net change in short-term borrowings                                   (2,257)            (67,676)
    Principal payments under capital lease obligations                    (3,369)             (4,106)
    Other                                                                    113                (423)
                                                                -----------------   -----------------
        Net cash flows used for financing activities                     (43,130)            (77,367)
                                                                -----------------   -----------------
-----------------------------------------------------------------------------------------------------
Cashflows used for investing activities:
    Construction and acquisition expenditures:
       Utility                                                           (41,638)            (39,160)
       Nonregulated businesses                                           (49,198)            (22,554)
    Nuclear decommissioning trust funds                                  (15,437)            (13,642)
    Shared savings expenditures                                           (4,247)             (1,808)
    Other                                                                  5,854               7,032
                                                                -----------------   -----------------
       Net cash flows used for investing activities                     (104,666)            (70,132)
                                                                -----------------   -----------------
-----------------------------------------------------------------------------------------------------
Net increase in cash and temporary cash investments                       22,356              34,774
                                                                -----------------   -----------------
-----------------------------------------------------------------------------------------------------
Cash and temporary cash investments at beginning of period                31,827              27,329
                                                                -----------------   -----------------
-----------------------------------------------------------------------------------------------------
                                                                -----------------   -----------------
Cash and temporary cash investments at end of period                    $ 54,183            $ 62,103
                                                                =================   =================
-----------------------------------------------------------------------------------------------------
Supplemental cash flow information:
    Cash paid during the period for:
       Interest                                                         $ 31,952            $ 32,237
                                                                =================   =================
       Income taxes                                                      $ 4,600            $ 11,892
                                                                =================   =================
    Noncash investing and financing activities:
       Capital lease obligations incurred                                $ 1,414             $ 1,039
                                                                =================   =================
-----------------------------------------------------------------------------------------------------

The accompanying Notes to Consolidated Financial Statements are an integral part
of these statements.
</TABLE>



                                       7


<PAGE>

                          INTERSTATE ENERGY CORPORATION

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)

1.     The interim  consolidated  financial statements included herein have been
       prepared by IEC, without audit,  pursuant to the rules and regulations of
       the  SEC.  Accordingly,  certain  information  and  footnote  disclosures
       normally  included in financial  statements  prepared in accordance  with
       generally accepted accounting  principles have been condensed or omitted,
       although  management  believes that the  disclosures are adequate to make
       the information  presented not  misleading.  The  consolidated  financial
       statements  include IEC and its consolidated  subsidiaries  (WP&L,  IESU,
       IPC, Resources and Corporate Services). These financial statements should
       be read in  conjunction  with  the  financial  statements  and the  notes
       thereto included in IEC's, IESU's and WP&L's latest Annual Report on Form
       10-K.

       In the  opinion  of  management,  all  adjustments,  which are normal and
       recurring  in  nature,  necessary  for a fair  presentation  of  (a)  the
       consolidated  results of operations  for the three months ended March 31,
       1999 and 1998, (b) the consolidated  financial position at March 31, 1999
       and December 31, 1998, and (c) the  consolidated  statement of cash flows
       for the three  months  ended  March 31,  1999 and 1998,  have been  made.
       Because of the seasonal  nature of IESU's,  WP&L's and IPC's  operations,
       results for the three  months  ended  March 31, 1999 are not  necessarily
       indicative  of results that may be expected for the year ending  December
       31, 1999.  Certain prior period amounts have been reclassified on a basis
       consistent with the 1999 presentation.

2.     IEC's  comprehensive  income,  and the components of other  comprehensive
       income (loss), net of taxes, were as follows (in thousands):
<TABLE>
<CAPTION>

                                                                        For the Three Months
                                                                           Ended March 31,
                                                                       1999              1998
                                                                   --------------   ---------------
<S>                                                                    <C>               <C>
            Net income                                                 $  41,744         $  28,875

               Other comprehensive income (loss):
                 Unrealized gain on securities, net of tax (1)
                                                                          75,031            61,829
                 Foreign currency translation adjustments
                                                                           (614)                55
                                                                   --------------   ---------------
                   Other comprehensive income                             74,417
                                                                                            61,884

                                                                   --------------   ---------------
            Comprehensive income                                       $ 116,161         $  90,759
                                                                   ==============   ===============

(1)    Primarily due to the  adjustment to the estimated fair value each quarter
       of IEC's investment in McLeod.

</TABLE>

      IESU and WP&L had no comprehensive income in the periods presented.


                                       8
<PAGE>



3.     Certain  financial  information  relating to IEC's  significant  business
       segments is presented below:
<TABLE>
<CAPTION>

                                         Regulated Domestic Utilities           Nonregulated                 IEC
                                  -------------------------------------------
                                   Electric     Gas      Other      Total        Businesses     Other   Consolidated
                                  ------------------------------------------------------------------------------------
                                                                     (in thousands)
<S>                                <C>        <C>         <C>       <C>               <C>         <C>        <C>
      Three Months Ended
      March 31, 1999
      --------------
      Operating revenues           $351,338   $133,684    $9,204    $494,226          $53,199     ($570)     $546,855
      Operating income (loss)        68,615     23,939     2,354      94,908           (1,836)      (85)       92,987
      Net income (loss)                                               44,767           (1,906)   (1,117)       41,744

      Three Months Ended
      March 31, 1998
      --------------
      Operating revenues           $357,751   $130,046    $8,409    $496,206          $60,322     ($245)     $556,283
      Operating income (loss)        55,837     22,376     1,831      80,044           (5,499)     (665)       73,880
      Net income (loss)                                               33,177           (3,999)     (303)       28,875
</TABLE>

       Resources'  (i.e.  the  nonregulated  businesses)  assets  increased $150
       million  during the first quarter of 1999,  primarily due to the increase
       in market value of its investment in McLeod and additional investments in
       foreign  entities.  Intersegment  revenues  were  not  material  to IEC's
       operations and there was no single  customer whose revenues  exceeded 10%
       or more of IEC's consolidated revenues.

4.     The  provisions  for  income  taxes  are  based on the  estimated  annual
       effective tax rate, which differs from the federal  statutory rate of 35%
       principally due to: state income taxes,  tax credits,  effects of utility
       rate making and certain nondeductible expenses.

5.     At March 31,  1999,  IEC had  $119.1  million of  investments  in foreign
       entities  on  its   Consolidated   Balance  Sheets  that  included:   (a)
       investments in several New Zealand utility  entities;  (b) investments in
       several  generation  facilities  in China;  and (c) an  investment  in an
       international   venture   capital  fund.   IEC  accounts  for  the  China
       investments  under the equity method and the other  investments under the
       cost method. The geographic concentration of IEC's investments in foreign
       entities at March 31, 1999,  included  investments of approximately $85.7
       million in New Zealand,  $32.9 million in China and $0.5 million in other
       countries.

6.     In October 1998,  the Board of Directors of IEC adopted a new  Shareowner
       Rights  Plan (new  plan) to replace  IEC's  former  plan that  expired on
       February 22,  1999.  The new plan was approved on January 15, 1999 by the
       SEC. On January 20, 1999,  the Board of Directors  declared a dividend of
       one common share  purchase  right  (right) on each  outstanding  share of
       IEC's common stock which was issued on February 22, 1999 to coincide with
       the  expiration  of the former  plan.  Rights  under the new plan will be
       exercisable  only if a person or group  acquires,  or  announces a tender
       offer to  acquire,  15% or more of IEC's  common  stock.  Each right will
       initially  entitle  shareowners  to buy  one-half  of one  share of IEC's
       common stock.  The rights will only be exercisable in multiples of two at
       an initial price of $95.00 per full share, subject to adjustment.  If any
       shareowner  acquires 15% or more of the outstanding  common stock of IEC,
       each right (subject to limitations)  will entitle its holder to purchase,
       at the right's then current  exercise price, a number of common shares of
       IEC or of the  acquirer  having a market  value at the time of twice  the
       right's per full share  exercise  price.  The Board of  Directors is also
       authorized to reduce the 15% thresholds to not less than 10%.


                                       9
<PAGE>

7.     Summary   financial   information   for  Resources  was  as  follows  (in
       thousands):

                                          March 31,
                                            1999
                                         ------------
       Current assets                      $84,950
       Non-current assets                  934,393
       Current liabilities                  40,468
       Non-current liabilities
         (excludes minority interest)      208,785
       Minority interest                     6,162

       Refer  to the  "Nonregulated  Businesses"  column  of Note 3 for  summary
       income statement data of Resources.

8.     At  the Annual  Shareowners  meeting  on May 19,  1999,  the  shareowners
       approved a proposal to change the name of the corporation from Interstate
       Energy  Corporation  to Alliant Energy  Corporation.  The name change was
       effective May 20, 1999.


                                       10
<PAGE>

                               IES UTILITIES INC.
                 CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)

                                            For the Three Months Ended March 31,
                                                 1999                  1998
-------------------------------------------------------------------------------
                                                       (in thousands)
Operating revenues:
  Electric utility                              $ 140,017           $ 140,649
  Gas utility                                      61,296              60,395
  Steam and other                                   7,952               7,234
                                                ---------           ---------
                                                  209,265             208,278
                                                ---------           ---------
-----------------------------------------------------------------------------
Operating expenses:
  Electric and steam production fuels              26,589              30,649
  Purchased power                                  13,150              11,049
  Cost of gas sold                                 37,912              37,657
  Other operation                                  47,439              47,002
  Maintenance                                       9,904              10,991
  Depreciation and amortization                    25,482              24,335
  Taxes other than income taxes                    12,616              12,306
                                                ---------           ---------
                                                  173,092             173,989
                                                ---------           ---------
-----------------------------------------------------------------------------

Operating income                                   36,173              34,289
                                                ---------           ---------
-----------------------------------------------------------------------------

Interest expense and other:
Interest expense                                   13,204              13,075
  Allowance for funds used during
   construction                                      (849)               (765)
  Miscellaneous, net                                 (857)                279
                                                ---------           ---------
                                                   11,498              12,589
                                                ---------           ---------
-----------------------------------------------------------------------------

Income before income taxes                         24,675              21,700
                                                ---------           ---------
-----------------------------------------------------------------------------

Income taxes                                       10,216              10,040
                                                ---------           ---------
-----------------------------------------------------------------------------

Net income                                         14,459              11,660
                                                ---------           ---------
-----------------------------------------------------------------------------

Preferred dividend requirements                       229                 229
                                                ---------           ---------
-----------------------------------------------------------------------------

Earnings available for common stock             $  14,230           $  11,431
                                                =========           =========
-----------------------------------------------------------------------------


The accompanying Notes to Consolidated Financial Statements are an integral part
of these statements.

                                       11

<PAGE>

                               IES UTILITIES INC.
                           CONSOLIDATED BALANCE SHEETS

                                               March 31,
                                                  1999            December 31,
ASSETS                                         (Unaudited)             1998
--------------------------------------------------------------------------------
                                                          (in thousands)
Property, plant and equipment:
  Utility -
    Plant in service -
      Electric                                  $ 2,148,059       $ 2,140,322
      Gas                                           199,209           198,488
      Steam                                          55,794            55,797
      Common                                        106,732           106,940
                                               -------------   ---------------
                                                  2,509,794         2,501,547
    Less - Accumulated depreciation               1,237,623         1,209,204
                                               -------------   ---------------
                                                  1,272,171         1,292,343
    Construction work in progress                    57,141            48,991
    Leased nuclear fuel, net of
     amortization                                    23,559            25,644
                                               -------------   ---------------
                                                  1,352,871         1,366,978
  Other property, plant and equipment,
    net of accumulated depreciation and
    amortization of $1,984 and $1,948,
    respectively                                      5,586             5,623
                                               -------------   ---------------
                                                  1,358,457         1,372,601
                                               -------------   ---------------
------------------------------------------------------------------------------
Current assets:
  Cash and temporary cash investments                   585             4,175
  Temporary cash investments with
     associated companies                                 -            53,729
  Accounts receivable:
    Customer, less allowance for doubtful
      accounts of $1,056 and $1,058,
      respectively                                   17,543            16,703
    Associated companies                              2,466             2,662
    Other, less allowance for doubtful
      accounts of $363 and $357,
      respectively                                   10,158            10,346
  Production fuel, at average cost                   13,306            11,863
  Materials and supplies, at average cost            25,972            25,591
  Gas stored underground, at average cost             5,887            12,284
  Regulatory assets                                  19,324            23,487
  Prepayments and other                               3,879             4,185
                                               -------------   ---------------
                                                     99,120           165,025
                                               -------------   ---------------
------------------------------------------------------------------------------
Investments:
  Nuclear decommissioning trust funds                95,398            91,691
  Other                                               6,236             6,019
                                               -------------   ---------------
                                                    101,634            97,710
                                               -------------   ---------------
------------------------------------------------------------------------------
Other assets:
  Regulatory assets                                 133,491           137,908
  Deferred charges and other                         15,201            15,734
                                               -------------   ---------------
                                                    148,692           153,642
                                               -------------   ---------------
------------------------------------------------------------------------------
Total assets                                    $ 1,707,903       $ 1,788,978
                                               =============   ===============
------------------------------------------------------------------------------

The accompanying Notes to Consolidated Financial Statements are an integral part
of these statements.


                                       12
<PAGE>

                               IES UTILITIES INC.
                     CONSOLIDATED BALANCE SHEETS (CONTINUED)
<TABLE>
<CAPTION>

                                                                                March 31,
                                                                                  1999               December 31,
CAPITALIZATION AND LIABILITIES                                                 (Unaudited)               1998
--------------------------------------------------------------------------------------------------------------------
                                                                             (in thousands, except share amounts)
<S>                                                                               <C>                   <C>
Capitalization:
  Common stock - $2.50 par value - authorized 24,000,000
    shares; 13,370,788 shares outstanding                                         $    33,427           $    33,427
  Additional paid-in capital                                                          279,042               279,042
  Retained earnings                                                                   245,626               275,372
                                                                            ------------------     -----------------
    Total common equity                                                               558,095               587,841
  Cumulative preferred stock, not mandatorily redeemable -
    $50 par value - authorized 466,406 shares; 366,406 shares outstanding              18,320                18,320
  Long-term debt (excluding current portion)                                          551,086               602,020
                                                                            ------------------     -----------------
                                                                                    1,127,501             1,208,181
                                                                            ------------------     -----------------
--------------------------------------------------------------------------------------------------------------------
Current liabilities:
  Current maturities and sinking funds                                                 51,140                50,140
  Capital lease obligations                                                            12,132                11,965
  Notes payable to associated companies                                                 9,694                     -
  Accounts payable                                                                     30,117                43,953
  Accounts payable to associated companies                                             13,930                22,487
  Accrued payroll and vacations                                                         9,311                 6,365
  Accrued interest                                                                     10,082                12,045
  Accrued taxes                                                                        64,480                55,295
  Accumulated refueling outage provision                                                9,020                 6,605
  Environmental liabilities                                                             5,660                 5,660
  Other                                                                                16,928                17,617
                                                                            ------------------     -----------------
                                                                                      232,494               232,132
                                                                            ------------------     -----------------
--------------------------------------------------------------------------------------------------------------------
Other long-term liabilities and deferred credits:
  Accumulated deferred income taxes                                                   224,893               224,510
  Accumulated deferred investment tax credits                                          28,603                29,243
  Environmental liabilities                                                            29,027                29,195
  Pension and other benefit obligations                                                27,283                25,655
  Capital lease obligations                                                            11,427                13,679
  Other                                                                                26,675                26,383
                                                                            ------------------     -----------------
                                                                                      347,908               348,665
                                                                            ------------------     -----------------
--------------------------------------------------------------------------------------------------------------------
Total capitalization and liabilities                                              $ 1,707,903           $ 1,788,978
                                                                            ==================     =================
--------------------------------------------------------------------------------------------------------------------

The accompanying Notes to Consolidated Financial Statements are an integral part
of these statements.
</TABLE>


                                       13
<PAGE>

                               IES UTILITIES INC.
                CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
<TABLE>
<CAPTION>

                                                                                     For the Three Months Ended March 31,
                                                                                          1999                1998
-------------------------------------------------------------------------------------------------------------------------
                                                                                                   (in thousands)
<S>                                                                                  <C>                 <C>
Cash flows from operating activities:
  Net income                                                                         $    14,459         $    11,660
  Adjustments to reconcile net income to net cash
   flows from operating activities:
     Depreciation and amortization                                                        25,482              24,335
     Amortization of leased nuclear fuel                                                   3,499               4,010
     Amortization of deferred energy efficiency expenditures                               6,064               6,070
     Deferred taxes and investment tax credits                                              (473)             (8,822)
     Refueling outage provision                                                            2,415               1,299
     Other                                                                                   146                 319
  Other changes in assets and liabilities:
     Accounts receivable                                                                    (456)              2,796
     Production fuel                                                                      (1,443)                197
     Materials and supplies                                                                 (381)             (1,249)
     Gas stored underground                                                                6,397              10,509
     Accounts payable                                                                    (22,393)            (12,292)
     Accrued taxes                                                                         9,185              13,262
     Adjustment clause balances                                                            4,809               9,466
     Benefit obligations and other                                                         5,776               5,449
                                                                                   ------------------   -----------------
       Net cash flows from operating activities                                           53,086              67,009
                                                                                   ------------------   -----------------
-------------------------------------------------------------------------------------------------------------------------
Cash flows used for financing activities:
    Common stock dividends declared                                                      (43,976)            (14,000)
    Dividends payable                                                                     (4,840)             14,000
    Preferred stock dividends                                                               (229)               (229)
    Reductions in long-term debt                                                         (50,000)                  -
    Net change in short-term borrowings                                                    9,694                   -
    Principal payments under capital lease obligations                                    (3,369)             (4,106)
    Other                                                                                     (3)                  -
                                                                                   ------------------  ------------------
      Net cash flows used for financing activities                                       (92,723)             (4,335)
                                                                                   ------------------  ------------------
-------------------------------------------------------------------------------------------------------------------------
Cash flows used for investing activities:
    Construction expenditures - utility                                                  (16,621)            (19,198)
    Nuclear decommissioning trust funds                                                   (1,502)             (1,502)
    Other                                                                                    441                  72
                                                                                   ------------------  ------------------
      Net cash flows used for investing activities                                       (17,682)            (20,628)
                                                                                   ------------------  ------------------
-------------------------------------------------------------------------------------------------------------------------
Net increase (decrease) in cash and temporary cash investments                           (57,319)             42,046
                                                                                   ------------------  ------------------
-------------------------------------------------------------------------------------------------------------------------
Cash and temporary cash investments at beginning of period                                57,904                 230
                                                                                   ------------------  ------------------
-------------------------------------------------------------------------------------------------------------------------
Cash and temporary cash investments at end of period                                 $       585         $    42,276
                                                                                   ==================  ==================
-------------------------------------------------------------------------------------------------------------------------
Supplemental cash flow information: Cash paid during the period for:
    Interest                                                                         $    13,989         $    12,378
                                                                                   ==================  ==================
    Income taxes                                                                     $     7,334         $    11,804
                                                                                   ==================  ==================
  Noncash investing and financing activities - Capital lease obligations incurred    $     1,414         $     1,039
                                                                                   ==================  ==================
-------------------------------------------------------------------------------------------------------------------------

The accompanying Notes to Consolidated Financial Statements are an integral part
of these statements.

</TABLE>


                                       14
<PAGE>


                               IES UTILITIES INC.

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)

       Except  as  modified  below,  the IEC  Notes  to  Consolidated  Financial
       Statements are incorporated by reference  insofar as they relate to IESU.
       IEC  Notes  5 and 6 do  not  relate  to  IESU  and,  therefore,  are  not
       incorporated by reference.

1.     The interim  consolidated  financial statements included herein have been
       prepared by IESU, without audit, pursuant to the rules and regulations of
       the  SEC.  Accordingly,  certain  information  and  footnote  disclosures
       normally  included in financial  statements  prepared in accordance  with
       generally accepted accounting  principles have been condensed or omitted,
       although  management  believes that the  disclosures are adequate to make
       the information  presented not  misleading.  The  consolidated  financial
       statements include IESU and its consolidated wholly-owned subsidiary, IES
       Ventures  Inc. IESU is a subsidiary of IEC.  These  financial  statements
       should be read in conjunction with the financial statements and the notes
       thereto included in IESU's latest Annual Report on Form 10-K.

       In the  opinion  of  management,  all  adjustments,  which are normal and
       recurring  in  nature,  necessary  for a fair  presentation  of  (a)  the
       consolidated  results of operations  for the three months ended March 31,
       1999 and 1998, (b) the consolidated  financial position at March 31, 1999
       and December 31, 1998, and (c) the  consolidated  statement of cash flows
       for the three  months  ended  March 31,  1999 and 1998,  have been  made.
       Because of the  seasonal  nature of IESU's  operations,  results  for the
       three  months  ended March 31,  1999 are not  necessarily  indicative  of
       results  that may be expected  for the year  ending  December  31,  1999.
       Certain prior period amounts have been reclassified on a basis consistent
       with the 1999 presentation.



                                       15
<PAGE>

                        WISCONSIN POWER AND LIGHT COMPANY
                  CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)

                                            For the Three Months Ended March 31,
                                                1999                    1998
------------------------------------------------------------------------------
                                                       (in thousands)
Operating revenues:
  Electric utility                           $  149,944            $   151,310
  Gas utility                                    51,794                 50,318
  Water                                           1,252                  1,175
                                             ----------            -----------
                                                202,990                202,803
                                             ----------            -----------
------------------------------------------------------------------------------
Operating expenses:
  Electric production fuels                      27,366                 28,897
  Purchased power                                24,000                 28,602
  Cost of gas sold                               31,181                 30,714
  Other operation                                26,108                 34,003
  Maintenance                                     9,103                  9,967
  Depreciation and amortization                  31,139                 29,258
  Taxes other than income taxes                   7,702                  7,711
                                             ----------            -----------
                                                156,599                169,152
                                             ----------            -----------
------------------------------------------------------------------------------
Operating income                                 46,391                 33,651
                                             ----------            -----------
------------------------------------------------------------------------------
Interest expense and other:
  Interest expense                                9,865                  8,383
  Allowance for funds used during
     construction                                  (923)                  (656)
  Miscellaneous, net                             (4,344)                (1,867)
                                             ----------            -----------
                                                  4,598                  5,860
                                             ----------            -----------
------------------------------------------------------------------------------

Income before income taxes                       41,793                 27,791
                                             ----------            -----------
------------------------------------------------------------------------------

Income taxes                                     15,505                 10,193
                                             ----------            -----------
------------------------------------------------------------------------------

Net income                                       26,288                 17,598
                                             ----------            -----------
------------------------------------------------------------------------------

Preferred dividend requirements                     828                    828
                                             ----------            -----------
------------------------------------------------------------------------------

Earnings available for common stock          $   25,460            $    16,770
                                             ==========            ===========
------------------------------------------------------------------------------

The accompanying Notes to Consolidated Financial Statements are an integral part
of these statements.


                                       16
<PAGE>

                        WISCONSIN POWER AND LIGHT COMPANY
                           CONSOLIDATED BALANCE SHEETS

                                                March 31,
                                                  1999             December 31,
ASSETS                                        (Unaudited)              1998
--------------------------------------------------------------------------------
                                                     (in thousands)
Property, plant and equipment:
  Utility -
    Plant in service -
      Electric                                 $ 1,847,950          $ 1,839,545
      Gas                                          246,188              244,518
      Water                                         26,584               26,567
      Common                                       219,715              219,268
                                             --------------    -----------------
                                                 2,340,437            2,329,898
    Less - Accumulated depreciation              1,199,761            1,168,830
                                             --------------    -----------------
                                                 1,140,676            1,161,068
    Construction work in progress                   63,950               56,994
    Nuclear fuel, net of amortization               17,151               18,671
                                             --------------    -----------------
                                                 1,221,777            1,236,733
  Other property, plant and equipment,
    net of accumulated depreciation and
    amortization of $44 for both years                 630                  630
                                             --------------    -----------------
                                                 1,222,407            1,237,363
                                             --------------    -----------------
--------------------------------------------------------------------------------
Current assets:
  Cash and temporary cash investments                9,496                1,811
  Accounts receivable:
    Customer                                         9,932               13,372
    Associated companies                             1,921                3,019
    Other                                            7,307                8,298
  Production fuel, at average cost                  14,851               20,105
  Materials and supplies, at average cost           21,117               20,025
  Gas stored underground, at average cost            5,924               10,738
  Regulatory assets                                  3,707                3,707
  Prepaid gross receipts tax                        16,882               22,222
  Other                                              1,413                6,987
                                             --------------    -----------------
                                                    92,550              110,284
                                             --------------    -----------------
--------------------------------------------------------------------------------
Investments:
  Nuclear decommissioning trust funds              149,627              134,112
  Other                                             15,476               15,960
                                             --------------    -----------------
                                                   165,103              150,072
                                             --------------    -----------------
--------------------------------------------------------------------------------
Other assets:
  Regulatory assets                                 74,788               76,284
  Deferred charges and other                       113,058              111,147
                                             --------------    -----------------
                                                   187,846              187,431
                                             --------------    -----------------
--------------------------------------------------------------------------------
Total assets                                   $ 1,667,906          $ 1,685,150
                                             ==============    =================
--------------------------------------------------------------------------------

The accompanying Notes to Consolidated Financial Statements are an integral part
of these statements.


                                       17
<PAGE>

                        WISCONSIN POWER AND LIGHT COMPANY
                     CONSOLIDATED BALANCE SHEETS (CONTINUED)
<TABLE>
<CAPTION>

                                                                     March 31,
                                                                        1999              December 31,
CAPITALIZATION AND LIABILITIES                                      (Unaudited)               1998
---------------------------------------------------------------------------------------------------------
                                                                   (in thousands, except share amounts)
<S>                                                                    <C>                   <C>
Capitalization:
  Common stock - $5 par value - authorized 18,000,000
    shares; 13,236,601 shares outstanding                              $    66,183           $    66,183
  Additional paid-in capital                                               199,438               199,438
  Retained earnings                                                        305,181               294,309
                                                                  -----------------     -----------------
    Total common equity                                                    570,802               559,930
                                                                  -----------------     -----------------

  Cumulative preferred stock, not mandatorily redeemable
    without par value - authorized 3,750,000 shares, maximum
    aggregate stated value $150,000,000:
      $100 stated value - 449,765 shares outstanding                        44,977                44,977
      $25 stated value - 599,460 shares outstanding                         14,986                14,986
                                                                  -----------------     -----------------
        Total cumulative preferred stock                                    59,963                59,963
                                                                  -----------------     -----------------

  Long-term debt (excluding current portion)                               414,603               414,579
                                                                  -----------------     -----------------
                                                                         1,045,368             1,034,472
                                                                  -----------------     -----------------
---------------------------------------------------------------------------------------------------------
Current liabilities:
  Variable rate demand bonds                                                56,975                56,975
  Notes payable                                                             50,000                50,000
  Notes payable to associated companies                                      1,102                26,799
  Accounts payable                                                          70,884                84,754
  Accounts payable to associated companies                                  16,468                20,315
  Accrued payroll and vacations                                              5,052                 5,276
  Accrued interest                                                           8,093                 6,863
  Accrued taxes                                                             16,502                   740
  Other                                                                     10,197                13,860
                                                                  -----------------     -----------------
                                                                           235,273               265,582
                                                                  -----------------     -----------------
---------------------------------------------------------------------------------------------------------
Other long-term liabilities and deferred credits:
  Accumulated deferred income taxes                                        243,750               245,489
  Accumulated deferred investment tax credits                               32,705                33,170
  Customer advances                                                         33,253                34,367
  Environmental liabilities                                                 11,644                11,683
  Other                                                                     65,913                60,387
                                                                  -----------------     -----------------
                                                                           387,265               385,096
                                                                  -----------------     -----------------
---------------------------------------------------------------------------------------------------------
Total capitalization and liabilities                                   $ 1,667,906           $ 1,685,150
                                                                  =================     =================
---------------------------------------------------------------------------------------------------------

The accompanying Notes to Consolidated Financial Statements are an integral part
of these statements.

</TABLE>

                                       18
<PAGE>

                        WISCONSIN POWER AND LIGHT COMPANY
                CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
<TABLE>
<CAPTION>

                                                                             For the Three Months Ended March 31,
                                                                                  1999                   1998
-------------------------------------------------------------------------------------------------------------------
                                                                                     (in thousands)
<S>                                                                          <C>                    <C>
Cash flows from operating activities:
  Net income                                                                 $   26,288             $   17,598
  Adjustments to reconcile net income to net cash
   flows from operating activities:
     Depreciation and amortization                                               31,139                 29,258
     Amortization of nuclear fuel                                                 1,525                  1,427
     Deferred taxes and investment tax credits                                   (1,578)                (1,607)
     Other                                                                       (1,617)                  (457)
  Other changes in assets and liabilities:
     Accounts receivable                                                          5,529                 15,460
     Production fuel                                                              5,254                  4,889
     Materials and supplies                                                      (1,092)                   (32)
     Gas stored underground                                                       4,814                  8,768
     Prepaid gross receipts tax                                                   5,340                  4,912
     Accounts payable                                                           (17,717)                (3,302)
     Accrued taxes                                                               15,762                 10,396
     Adjustment clause balances                                                   7,157                  3,691
     Benefit obligations and other                                                2,814                   (361)
                                                                   ---------------------  ---------------------
       Net cash flows from operating activities                                  83,618                 90,640
                                                                   ---------------------  ---------------------
---------------------------------------------------------------------------------------------------------------
Cash flows used for financing activities:
    Common stock dividends                                                      (14,588)               (14,586)
    Preferred stock dividends                                                      (828)                  (828)
    Net change in short-term borrowings                                         (25,697)               (42,500)
                                                                   ---------------------  ---------------------
      Net cash flows used for financing activities                              (41,113)               (57,914)
                                                                   ---------------------  ---------------------
---------------------------------------------------------------------------------------------------------------
Cash flows used for investing activities:
    Construction expenditures - utility                                         (18,967)               (15,584)
    Nuclear decommissioning trust funds                                         (13,935)               (12,140)
    Shared savings expenditures                                                  (2,519)                (1,808)
    Other                                                                           601                    477
                                                                   ---------------------  ---------------------
      Net cash flows used for investing activities                              (34,820)               (29,055)
                                                                   ---------------------  ---------------------
---------------------------------------------------------------------------------------------------------------
Net increase in cash and temporary cash investments                               7,685                  3,671
                                                                   ---------------------  ---------------------
---------------------------------------------------------------------------------------------------------------
Cash and temporary cash investments at beginning of period                        1,811                  2,492
                                                                   ---------------------  ---------------------
---------------------------------------------------------------------------------------------------------------
Cash and temporary cash investments at end of period                            $ 9,496                $ 6,163
                                                                   =====================  =====================
---------------------------------------------------------------------------------------------------------------
Supplemental cash flow information:
  Cash paid (refunded) during the period for:
    Interest                                                                    $ 8,468                $ 8,150
                                                                   =====================  =====================
    Income taxes                                                                 $ (357)               $ 1,668
                                                                   =====================  =====================
---------------------------------------------------------------------------------------------------------------

The accompanying Notes to Consolidated Financial Statements are an integral part
of these statements.

</TABLE>

                                       19
<PAGE>


                        WISCONSIN POWER AND LIGHT COMPANY

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)

       Except  as  modified  below,  the IEC  Notes  to  Consolidated  Financial
       Statements are incorporated by reference  insofar as they relate to WP&L.
       IEC  Notes  5 and 6 do  not  relate  to  WP&L  and,  therefore,  are  not
       incorporated by reference.

1.     The interim  consolidated  financial statements included herein have been
       prepared by WP&L, without audit, pursuant to the rules and regulations of
       the  SEC.  Accordingly,  certain  information  and  footnote  disclosures
       normally  included in financial  statements  prepared in accordance  with
       generally accepted accounting  principles have been condensed or omitted,
       although  management  believes that the  disclosures are adequate to make
       the information  presented not  misleading.  The  consolidated  financial
       statements  include  WP&L  and  its  consolidated  subsidiary.  WP&L is a
       subsidiary  of  IEC.  These  financial   statements  should  be  read  in
       conjunction with the financial  statements and the notes thereto included
       in WP&L's latest Annual Report on Form 10-K.

       In the  opinion  of  management,  all  adjustments,  which are normal and
       recurring  in  nature,  necessary  for a fair  presentation  of  (a)  the
       consolidated  results of operations  for the three months ended March 31,
       1999 and 1998, (b) the consolidated  financial position at March 31, 1999
       and December 31, 1998, and (c) the  consolidated  statement of cash flows
       for the three  months  ended  March 31,  1999 and 1998,  have been  made.
       Because of the  seasonal  nature of WP&L's  operations,  results  for the
       three  months  ended March 31,  1999 are not  necessarily  indicative  of
       results  that may be expected  for the year  ending  December  31,  1999.
       Certain prior period amounts have been reclassified on a basis consistent
       with the 1999 presentation.


                                       20
<PAGE>


                                   SIGNATURES

Pursuant to the  requirements  of the Securities  Exchange Act of 1934,  Alliant
Energy  Corporation,  IES Utilities  Inc. and Wisconsin  Power and Light Company
have  each  duly  caused  this  amendment  to be  signed  on its  behalf  by the
undersigned thereunto duly authorized on the 1st day of November 1999.


ALLIANT ENERGY CORPORATION
Registrant


By: /s/ John E. Ebright                   Vice President-Controller
John E. Ebright                              (Principal Accounting Officer)


IES UTILITIES INC.
Registrant


By: /s/ John E. Ebright                   Vice President-Controller
John E. Ebright                              (Principal Accounting Officer)


WISCONSIN POWER AND LIGHT COMPANY
Registrant


By: /s/ John E. Ebright                   Vice President-Controller
John E. Ebright                               (Principal Accounting Officer)


                                       21