Exhibit No. 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,
|                                                                       |  | 2007                    |       | 2006 |   | 2005  |  | 2004 |       | 2003
|                                                                       |  | (dollars in millions)  
|Earnings as defined for fixed charges calculation                      |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|Add:                                                                   |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|Pre-tax income from continuing operations(a)                           |  | $                       | 1,014 |      | $ | 890   |  | $    | 980   |      | $ | 910   |  | $ | 783  
|Fixed charges                                                          |  |                         | 329   |      |   | 502   |  |      | 1,159 |      |   | 1,433 |  |   | 1,620
|Distributed income of equity investees                                 |  |                         |      |      |   | 215   |  |      | 473   |      |   | 140   |  |   | 263  
|Deduct:                                                                |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|Preference security dividend requirements of consolidated subsidiaries |  |                         |      |      |   | 7     |  |      | 27    |      |   | 31    |  |   | 139  
|Interest capitalized(b)                                                |  |                         | 22    |      |   | 18    |  |      | 23    |      |   | 18    |  |   | 58   
|                                                                       |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|Total earnings (as defined for the Fixed Charges calculation)          |  | $                       | 1,321 |      | $ | 1,582 |  | $    | 2,562 |      | $ | 2,434 |  | $ | 2,469
|                                                                       |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|Fixed charges:                                                         |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|Interest on debt, including capitalized portions                       |  | $                       | 314   |      | $ | 481   |  | $    | 1,096 |      | $ | 1,365 |  | $ | 1,441
|Estimate of interest within rental expense                             |  |                         | 15    |      |   | 14    |  |      | 36    |      |   | 37    |  |   | 40   
|Preference security dividend requirements of consolidated subsidiaries |  |                         |      |      |   | 7     |  |      | 27    |      |   | 31    |  |   | 139  
|                                                                       |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|Total fixed charges                                                    |  | $                       | 329   |      | $ | 502   |  | $    | 1,159 |      | $ | 1,433 |  | $ | 1,620
|                                                                       |  |                         |       |      |   |       |  |      |       |      |   |       |  |   |      
|Ratio of earnings to fixed charges                                     |  |                         | 4.0   |      |   | 3.2   |  |      | 2.2   |      |   | 1.7   |  |   | 1.5  



|(a) | Excludes minority interest expense 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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