Exhibit 12

COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES

The ratio of earnings to fixed charges is calculated using the Securities and Exchange Commission guidelines.



|                                                                       |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|---------------------------------------------------------------------- |  | ----------------------- | ----- | ---- | - | ----- |  | ---- | ----- | ---- | - | ----- |  | - | -----
|                                                                       |  | Year Ended December 31,
|                                                                       |  | 2009                    |       | 2008 |   | 2007  |  | 2006 |       | 2005
|                                                                       |  | (dollars in millions)  
|                                                                       |  |                         |       |      |  
|Earnings as defined for fixed charges calculation                      |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|Add:                                                                   |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|Pre-tax income from continuing operations(a)                           |  | $                       | 1,080 |      | $ | 1,065 |  | $    | 1,014 |      | $ | 890   |  | $ | 980  
|Fixed charges                                                          |  |                         | 412   |      |   | 402   |  |      | 329   |      |   | 502   |  |   | 1,159
|Distributed income of equity investees                                 |  |                         |      |      |   |      |  |      |      |      |   | 215   |  |   | 473  
|Deduct:                                                                |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|Preference security dividend requirements of consolidated subsidiaries |  |                         |      |      |   |      |  |      |      |      |   | 7     |  |   | 27   
|Interest capitalized(b)                                                |  |                         | 65    |      |   | 46    |  |      | 22    |      |   | 18    |  |   | 23   
|                                                                       |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|Total earnings (as defined for the Fixed Charges calculation)          |  | $                       | 1,427 |      | $ | 1,421 |  | $    | 1,321 |      | $ | 1,582 |  | $ | 2,562
|                                                                       |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|                                                                       |  |                         |       |      |  
|Fixed charges:                                                         |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|Interest on debt, including capitalized portions                       |  | $                       | 395   |      | $ | 376   |  | $    | 314   |      | $ | 481   |  | $ | 1,096
|Estimate of interest within rental expense                             |  |                         | 17    |      |   | 26    |  |      | 15    |      |   | 14    |  |   | 36   
|Preference security dividend requirements of consolidated subsidiaries |  |                         |      |      |   |      |  |      |      |      |   | 7     |  |   | 27   
|                                                                       |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|Total fixed charges                                                    |  | $                       | 412   |      | $ | 402   |  | $    | 329   |      | $ | 502   |  | $ | 1,159
|                                                                       |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|                                                                       |  |                         |       |      |  
|Ratio of earnings to fixed charges                                     |  |                         | 3.5   |      |   | 3.5   |  |      | 4.0   |      |   | 3.2   |  |   | 2.2  



|(a) | Excludes net income (loss) attributable to noncontrolling interests and income or loss from equity investees.
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|(b) | Excludes equity costs related to Allowance for Funds Used During Construction that are included in Other Income and Expenses in the Consolidated Statements of
Operations.
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