| Schedule of Financial Data for Segments |
The tables below show our financial data for our segments for the periods indicated (in millions). | | | | | | | | | | | | | | | | | | | | | | Three Months Ended September 30, 2015 | | West | | Texas | | East | | Consolidation and Elimination | | Total | Revenues from external customers | $ | 736 |
| | $ | 709 |
| | $ | 503 |
| | $ | — |
| | $ | 1,948 |
| Intersegment revenues | 1 |
| | 4 |
| | 3 |
| | (8 | ) | | — |
| Total operating revenues | $ | 737 |
| | $ | 713 |
| | $ | 506 |
| | $ | (8 | ) | | $ | 1,948 |
| Commodity Margin | $ | 385 |
| | $ | 264 |
| | $ | 325 |
| | $ | — |
| | $ | 974 |
| Add: Mark-to-market commodity activity, net and other(1) | 68 |
| | (98 | ) | | (62 | ) | | (7 | ) | | (99 | ) | Less: | | | | | | | | | | Plant operating expense | 87 |
| | 62 |
| | 57 |
| | (6 | ) | | 200 |
| Depreciation and amortization expense | 61 |
| | 58 |
| | 48 |
| | (1 | ) | | 166 |
| Sales, general and other administrative expense | 7 |
| | 15 |
| | 10 |
| | 1 |
| | 33 |
| Other operating expenses | 8 |
| | 2 |
| | 8 |
| | (2 | ) | | 16 |
| (Income) from unconsolidated investments in power plants | — |
| | — |
| | (6 | ) | | — |
| | (6 | ) | Income from operations | 290 |
| | 29 |
| | 146 |
| | 1 |
| | 466 |
| Interest expense, net of interest income | | | | | | | | | 158 |
| Other (income) expense, net | | | | | | | | | 1 |
| Income before income taxes | | | | | | | | | $ | 307 |
|
| | | | | | | | | | | | | | | | | | | | | | Three Months Ended September 30, 2014 | | West | | Texas | | East | | Consolidation and Elimination | | Total | Revenues from external customers | $ | 714 |
| | $ | 985 |
| | $ | 488 |
| | $ | — |
| | $ | 2,187 |
| Intersegment revenues | 1 |
| | 4 |
| | 2 |
| | (7 | ) | | — |
| Total operating revenues | $ | 715 |
| | $ | 989 |
| | $ | 490 |
| | $ | (7 | ) | | $ | 2,187 |
| Commodity Margin(2) | $ | 361 |
| | $ | 346 |
| | $ | 237 |
| | $ | — |
| | $ | 944 |
| Add: Mark-to-market commodity activity, net and other(1) | 41 |
| | (64 | ) | | 4 |
| | (6 | ) | | (25 | ) | Less: | | | | | | | | | | Plant operating expense | 91 |
| | 77 |
| | 55 |
| | (8 | ) | | 215 |
| Depreciation and amortization expense | 65 |
| | 51 |
| | 38 |
| | (1 | ) | | 153 |
| Sales, general and other administrative expense | 11 |
| | 18 |
| | 8 |
| | — |
| | 37 |
| Other operating expenses | 12 |
| | 1 |
| | 6 |
| | 4 |
| | 23 |
| Impairment losses | — |
| | — |
| | 123 |
| | — |
| | 123 |
| (Gain) on sale of assets, net | — |
| | — |
| | (753 | ) | | — |
| | (753 | ) | (Income) from unconsolidated investments in power plants | — |
| | — |
| | (5 | ) | | — |
| | (5 | ) | Income from operations | 223 |
| | 135 |
| | 769 |
| | (1 | ) | | 1,126 |
| Interest expense, net of interest income | | | | | | | | | 154 |
| Debt extinguishment costs and other (income) expense, net | | | | | | | | | 344 |
| Income before income taxes | | | | | | | | | $ | 628 |
|
| | | | | | | | | | | | | | | | | | | | | | Nine Months Ended September 30, 2015 | | West | | Texas | | East | | Consolidation and Elimination | | Total | Revenues from external customers | $ | 1,672 |
| | $ | 1,860 |
| | $ | 1,504 |
| | $ | — |
| | $ | 5,036 |
| Intersegment revenues | 3 |
| | 12 |
| | 7 |
| | (22 | ) | | — |
| Total operating revenues | $ | 1,675 |
| | $ | 1,872 |
| | $ | 1,511 |
| | $ | (22 | ) | | $ | 5,036 |
| Commodity Margin | $ | 843 |
| | $ | 583 |
| | $ | 740 |
| | $ | — |
| | $ | 2,166 |
| Add: Mark-to-market commodity activity, net and other(3) | 173 |
| | (47 | ) | | (84 | ) | | (21 | ) | | 21 |
| Less: | | | | | | | | | | Plant operating expense | 313 |
| | 233 |
| | 206 |
| | (20 | ) | | 732 |
| Depreciation and amortization expense | 193 |
| | 157 |
| | 135 |
| | (1 | ) | | 484 |
| Sales, general and other administrative expense | 23 |
| | 47 |
| | 29 |
| | 1 |
| | 100 |
| Other operating expenses | 28 |
| | 6 |
| | 24 |
| | (2 | ) | | 56 |
| (Income) from unconsolidated investments in power plants | — |
| | — |
| | (18 | ) | | — |
| | (18 | ) | Income from operations | 459 |
| | 93 |
| | 280 |
| | 1 |
| | 833 |
| Interest expense, net of interest income | | | | | | | | | 468 |
| Debt modification and extinguishment costs and other (income) expense, net | | | | | | | | | 40 |
| Income before income taxes | | | | | | | | | $ | 325 |
|
| | | | | | | | | | | | | | | | | | | | | | Nine Months Ended September 30, 2014 | | West | | Texas | | East | | Consolidation and Elimination | | Total | Revenues from external customers | $ | 1,692 |
| | $ | 2,592 |
| | $ | 1,807 |
| | $ | — |
| | $ | 6,091 |
| Intersegment revenues | 4 |
| | 19 |
| | 46 |
| | (69 | ) | | — |
| Total operating revenues | $ | 1,696 |
| | $ | 2,611 |
| | $ | 1,853 |
| | $ | (69 | ) | | $ | 6,091 |
| Commodity Margin(2) | $ | 791 |
| | $ | 644 |
| | $ | 786 |
| | $ | — |
| | $ | 2,221 |
| Add: Mark-to-market commodity activity, net and other(3) | 91 |
| | 74 |
| | (31 | ) | | (23 | ) | | 111 |
| Less: | | | | | | | | | | Plant operating expense | 291 |
| | 250 |
| | 237 |
| | (24 | ) | | 754 |
| Depreciation and amortization expense | 183 |
| | 141 |
| | 129 |
| | — |
| | 453 |
| Sales, general and other administrative expense | 28 |
| | 48 |
| | 32 |
| | — |
| | 108 |
| Other operating expenses | 39 |
| | 4 |
| | 22 |
| | 1 |
| | 66 |
| Impairment losses | — |
| | — |
| | 123 |
| | — |
| | 123 |
| (Gain) on sale of assets, net | — |
| | — |
| | (753 | ) | | — |
| | (753 | ) | (Income) from unconsolidated investments in power plants | — |
| | — |
| | (18 | ) | | — |
| | (18 | ) | Income from operations | 341 |
|
| 275 |
|
| 983 |
|
| — |
| | 1,599 |
| Interest expense, net of interest income | | | | | | | | | 486 |
| Debt extinguishment costs and other (income) expense, net | | | | | | | | | 361 |
| Income before income taxes | | | | | | | | | $ | 752 |
|
_________ | | (1) | Includes $41 million and $49 million of lease levelization and $4 million and $4 million of amortization expense for the three months ended September 30, 2015 and 2014, respectively. |
| | (2) | Commodity Margin related to the six power plants sold in our East segment on July 3, 2014, was not significant for the three months ended September 30, 2014. The Commodity Margin related to those power plants was $81 million for the nine months ended September 30, 2014. |
| | (3) | Includes $(1) million and $(7) million of lease levelization and $11 million and $11 million of amortization expense for the nine months ended September 30, 2015 and 2014, respectively. |
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