At December 31, 2011, cash and cash equivalents decreased $811 million from December 31, 2010 to $1.7 billion.
The decrease in cash and cash equivalents was due to $2.9 billion of cash provided by operating activities, $4.9 billion of cash used for investing activities, $1.41 billion of cash provided by financing activities, an unfavorable effect of foreign currency exchange rates on cash of $122 million and a $79 million increase in cash of discontinued and held-for-sale businesses.
## Table 0 ##
Operating Activities Operating cash flow for the year ended December 31, 2012 resulted primarily from the net loss adjusted for non-cash items, principally gains and losses on sales and disposals and impairment charges, depreciation and amortization and deferred income taxes, partially offset by a net use of cash for operating activities of $68 million in operating assets and liabilities.
Other assets increased $589 million primarily due to an increase in noncurrent regulatory assets at Eletropaulo, resulting from higher priced energy purchases, regulatory charges and transmission costs which are recoverable through future tariff and the establishment of a noncurrent note receivable at Cartagena in Spain following the arbitration settlement, prior to its deconsolidation.
Accounts receivable increased $241 million primarily due to lower collections at Eletropaulo and Andres as well as an increase in revenue at Sul and Kelanitissa.
Net income tax payables decreased $47 million primarily from payments of income taxes exceeding accruals for new current tax liabilities.
These uses of operating cash flows were offset by an increase of $335 million in other liabilities primarily due to an increase in noncurrent regulatory liabilities at Eletropaulo related to the tariff reset.
Accounts payable and other current liabilities increased $330 million primarily due to an increase in current regulatory liabilities at Eletropaulo driven by the tariff reset, offset by a decrease in other current liabilities arising from value added tax payments.
Prepaid expenses and other current assets provided $120 million primarily due to the recovery of value added taxes at our construction projects in Chile.
Net cash provided by operating activities was $2.9 billion for the year ended December 31, 2011.
Operating cash flow resulted primarily from net income adjusted for non-cash items, principally depreciation and amortization, contingencies, deferred income taxes, losses on the extinguishment of debt, gains and losses on sales and disposals and impairment charges as well as a net favorable change of $52 million in operating assets and liabilities.
Other liabilities increased $351 million primarily due to an increase in noncurrent regulatory liabilities at Eletropaulo and Sul as the result of lower prices paid for energy purchases compared with the charges recovered through the tariff.
Accounts payable and other current liabilities increased $322 million primarily driven by an increase in current regulatory liabilities at Eletropaulo driven by the tariff reset, partially offset by the amount returned to consumers for regulatory liabilities and VAT on commercial losses reversal, as well as an increase in accrued interest on recourse debt at the Parent Company.
Income tax payables, net increased $166 million primarily due to accruals for new current tax liabilities offset by payments of income taxes.
These favorable changes were partially offset by increases of $403 million in other assets, $236 million in accounts receivable and $141 million in inventory.
The increase in other assets was mainly explained by an increase in noncurrent regulatory assets at Eletropaulo, resulting from higher priced energy purchases, transmission costs and regulatory charges compared with charges recovered through the tariff.
The increase in accounts receivable was primarily due to an increase in amounts billed at several businesses including Eletropaulo and new plants at Maritza and Angamos.
The increase in inventory was primarily driven by higher coal purchases at Gener as well as increased inventory at Angamos as it started operations in 2011.
Net cash provided by operating activities was $3.5 billion for the year ended December 31, 2010.
Operating cash flow resulted primarily from net income adjusted for non-cash items, principally depreciation and
CORPORATE AND SHAREHOLDER INFORMATION Home Office CarMax, Inc.  12800 Tuckahoe Creek Parkway Richmond, Virginia 23238 Telephone: (804) 747-0422 Website www.
carmax.
com Annual Shareholders’ Meeting Tuesday, June 24, 2008, at 8:30 a. m.  EDT The Richmond Marriott West Hotel 4240 Dominion Boulevard Glen Allen, Virginia 23060 Stock Information CarMax, Inc.  common stock is traded on the New York Stock Exchange under the ticker symbol KMX.
At February 29, 2008, there were approximately 7,000 CarMax shareholders of record.
Quarterly Stock Price Range The following table sets forth by fiscal quarter the high and low reported prices of our common stock for the last two fiscal years, adjusted for the March 2007 2-for-1 stock split.
## Table 1 ##
Dividend Policy To date, we have not paid a cash dividend on our common stock.
We presently intend to retain our net earnings for use in our operations and for geographic expansion and, therefore, we do not anticipate paying any cash dividends in the foreseeable future.
Transfer Agent and Registrar Contact our transfer agent for questions regarding your stock certificates, including changes of address, name or ownership; lost certificates; or to consolidate multiple accounts.
Wells Fargo Bank, N. A.  P. O.
Box 64854 South St.  Paul, Minnesota 55164-0854 Toll free: (800) 468-9716 Hearing impaired: (651) 450-4144 www.
wellsfargo.
com/shareownerservices Independent Auditors KPMG LLP 1021 East Cary Street, Suite 2000 Richmond, Virginia 23219-4023 Financial Information For quarterly sales and earnings information, financial reports, filings with the Securities and Exchange Commission (including Form 10-K), news releases and other investor information, please visit our investor website at: investor.
carmax.
com Information may also be obtained from the Investor Relations Department at: Email: investor_relations@carmax.
com Telephone: (804) 747-0422, ext.4489 CEO and CFO Certifications Our chief executive officer and chief financial officer have filed with the SEC the certifications required by Section 302 of the Sarbanes-Oxley Act of 2002 regarding the quality of our public disclosure.
These certifications are included as exhibits to the Annual Report on Form 10-K for fiscal 2008.
In addition, our chief executive officer annually certifies to the NYSE that he is not aware of any violation by CarMax of the NYSE’s corporate governance listing standards.
This certification was submitted, without qualification, as required after the 2007 annual meeting of CarMax’s shareholders.
Corporate Governance Information Copies of the CarMax Corporate Governance Guidelines, the Code of Conduct, and the charters for each of the Audit Committee, Nominating and Governance Committee and Compensation and Personnel Committee are available from our investor website, at investor.
carmax.
com, under the corporate governance tab.
Alternatively, shareholders may obtain, without charge, copies of these documents by writing to Investor Relations at the CarMax home office.
Investor Relations Security analysts and investors are invited to contact: Katharine Kenny, Assistant Vice President, Investor Relations Telephone: (804) 935-4591 Email: katharine_kenny@carmax.
com General Information Members of the media and others seeking general information about CarMax should contact: Lisa Van Riper, Assistant Vice President, Public Affairs Telephone: (804) 935-4594 Email: lisa_vanriper@carmax.
com CARMAX, CARMAX THE AUTO SUPERSTORE,THE CARMAX ADVANTAGE, 5-DAY MONEY-BACK GUARANTEE (and design), VALUMAX and CARMAX.
COM are all registered trademarks or service marks of CarMax.
Other company, product and service names may be trademarks or service marks of their respective owners.
Design: VIVO Design, Inc.  Store photography: Jeff Zaruba Printing: Peake DeLancey Printers and RR Donnelley
The following table summarizes NRG's U. S.  Coal capacity and the corresponding revenues and average natural gas prices and positions resulting from Coal hedge agreements extending beyond December 31, 2013, and through 2018 for the East region:
## Table 2 ##
(a) Net Coal capacity represents nominal summer net MW capacity of power generated as adjusted for the Company's ownership position excluding capacity from inactive/mothballed units, see Item 2 - Properties for units scheduled to be deactivated.
(b) Forecasted generation dispatch output (MWh) based on forward price curves as of December 31, 2013, which is then divided by number of hours in a given year to arrive at MW capacity.
The dispatch takes into account planned and unplanned outage assumptions.
(c) Includes amounts under power sales contracts and natural gas hedges.
The forward natural gas quantities are reflected in equivalent MWh based on forward market implied heat rate as of December 31, 2013, and then combined with power sales to arrive at equivalent MWh hedged which is then divided by number of hours in given year to arrive at MW hedged.
The Coal Sales include swaps and delta of options sold which is subject to change.
For detailed information on the Company's hedging methodology through use of derivative instruments, see discussion in Item 15 - Note 5, Accounting for Derivative Instruments and Hedging Activities, to the Consolidated Financial Statements.
Includes inter-segment sales from the Company's wholesale power generation business to the Retail Business.
(d) Percentage hedged is based on total Coal sales as described in (c) above divided by the forecasted Coal capacity.
(e) Represents U. S.  Coal sales, including energy revenue and demand charges, excluding revenues derived from capacity auctions.
Retail Operations In 2013, the Company's Retail Business sold electricity to residential, commercial and industrial consumers at either fixed, indexed or variable prices.
Residential and smaller commercial consumers typically contract for terms ranging from one month to two years while industrial contracts are often between one year and five years in length.
In 2013, the Company's Retail Business sold approximately 60 TWhs of electricity.
In any given year, the quantity of TWh sold can be affected by weather, economic conditions and competition.
The wholesale supply is typically purchased as the load is contracted in order to secure profit margin.
The wholesale supply is purchased from a combination of NRG's wholesale portfolio and other third parties, depending on the existing hedge position for the NRG wholesale portfolio at the time.
The ability to choose supply from the market or the Company's portfolio allows for an optimal combination to support and stabilize retail margins.
Table of Contents QUALCOMM Incorporated NOTES TO CONSOLIDATED FINANCIAL STATEMENTS suboptimal exercise factor are based on the Company’s historical option cancellation and employee exercise information, respectively.
The expected life of employee stock options is a derived output of the binomial model and is impacted by all of the underlying assumptions used by the Company.
The weighted-average expected life of employee stock options granted, as derived from the binomial model, was 5.5 years, 5.6 years and 5.9 years during fiscal 2010, 2009 and 2008, respectively.
The grant-date fair values of RSUs are estimated based on the fair market values of the underlying stock on the dates of grant.
The weighted-average estimated fair values of employee RSUs granted during fiscal 2010 and 2008 were $35.61 and $54.42 per share, respectively.
No RSUs were granted in fiscal 2009.
Shares are issued on the vesting dates net of the amount of shares needed to satisfy statutory tax withholding requirements to be paid by the Company on behalf of the employees.
As a result, the actual number of shares issued will be fewer than the actual number of RSUs outstanding.
Share-based compensation expense is adjusted to exclude amounts related to share-based awards that are expected to be forfeited.
The annual pre-vest forfeiture rate for stock options and RSUs granted in fiscal 2010 was estimated to be approximately 3% based on historical experience.
The effect of pre-vest forfeitures on the Company’s recorded expense in fiscal 2010, 2009 and 2008 for awards granted prior to fiscal 2010 was negligible due to the predominantly monthly vesting of stock options that were granted in those periods.
Total estimated share-based compensation expense, related to all of the Company’s share-based awards, was comprised as follows (in millions):

<table><tr><td></td><td></td><td></td><td></td><td colspan="2">$ Change</td></tr><tr><td></td><td>2012</td><td>2011</td><td>2010</td><td>2012 vs. 2011</td><td>2011 vs. 2010</td></tr><tr><td></td><td colspan="5">(in millions)</td></tr><tr><td>Net cash provided by (used in) operating activities</td><td>$2,901</td><td>$2,884</td><td>$3,465</td><td>$17</td><td>$-581</td></tr><tr><td>Net cash provided by (used in) investing activities</td><td>-1,023</td><td>-4,906</td><td>-2,040</td><td>3,883</td><td>-2,866</td></tr><tr><td>Net cash provided by (used in) financing activities</td><td>-1,739</td><td>1,412</td><td>-706</td><td>-3,151</td><td>2,118</td></tr></table>
<table><tr><td></td><td>FirstQuarter</td><td>SecondQuarter</td><td>ThirdQuarter</td><td>FourthQuarter</td></tr><tr><td>Fiscal 2008</td><td></td><td></td><td></td><td></td></tr><tr><td>High</td><td>$27.75</td><td>$27.42</td><td>$25.38</td><td>$23.47</td></tr><tr><td>Low</td><td>$22.63</td><td>$20.33</td><td>$18.67</td><td>$15.81</td></tr><tr><td>Fiscal 2007</td><td></td><td></td><td></td><td></td></tr><tr><td>High</td><td>$18.20</td><td>$18.95</td><td>$23.99</td><td>$29.44</td></tr><tr><td>Low</td><td>$15.14</td><td>$14.85</td><td>$18.59</td><td>$23.10</td></tr></table>
<table><tr><td>East</td><td>2014</td><td>2015</td><td>2016</td><td>2017</td><td>2018</td><td>AnnualAverage for2014-2018</td></tr><tr><td></td><td colspan="6">(Dollars in millions unless otherwise stated)</td></tr><tr><td>Net Coal Capacity (MW)<sup>(a)</sup></td><td>6,787</td><td>6,255</td><td>5,433</td><td>4,992</td><td>4,992</td><td>5,692</td></tr><tr><td>Forecasted Coal Capacity (MW)<sup>(b)</sup></td><td>3,215</td><td>2,276</td><td>1,766</td><td>1,682</td><td>1,718</td><td>2,132</td></tr><tr><td>Total Coal Sales (MW)<sup>(c)</sup></td><td>2,607</td><td>948</td><td>482</td><td>371</td><td>—</td><td>881</td></tr><tr><td>Percentage Coal Capacity Sold Forward<sup>(d)</sup></td><td>81%</td><td>42%</td><td>27%</td><td>22%</td><td>—%</td><td>41%</td></tr><tr><td>Total Forward Hedged Revenues<sup>(e)</sup></td><td>$1,339</td><td>$478</td><td>$258</td><td>$167</td><td>$—</td><td></td></tr><tr><td>Weighted Average Hedged Price ($ per MWh)<sup>(e)</sup></td><td>$58.65</td><td>$57.60</td><td>$61.08</td><td>$51.21</td><td>$—</td><td></td></tr><tr><td>Average Equivalent Natural Gas Price ($ per MMBtu)</td><td>$5.58</td><td>$5.22</td><td>$5.36</td><td>$4.53</td><td>$—</td><td></td></tr><tr><td>Gas Price Sensitivity Up $0.50/MMBtu on Coal Units</td><td>$97</td><td>$112</td><td>$94</td><td>$101</td><td>$117</td><td></td></tr><tr><td>Gas Price Sensitivity Down $0.50/MMBtu on Coal Units</td><td>$-47</td><td>$-66</td><td>$-56</td><td>$-58</td><td>$-75</td><td></td></tr><tr><td>Heat Rate Sensitivity Up 1 MMBtu/MWh on Coal Units</td><td>$84</td><td>$122</td><td>$96</td><td>$99</td><td>$102</td><td></td></tr><tr><td>Heat Rate Sensitivity Down 1 MMBtu/MWh on Coal Units</td><td>$-40</td><td>$-83</td><td>$-68</td><td>$-67</td><td>$-68</td><td></td></tr></table>

Question: What is the average increasing rate of Weighted Average Hedged Price ($ per MWh) between 2015 and 2016?