| Schedule of Financial Data for Segments |
The tables below show our financial data for our segments for the periods indicated (in millions). | | | | | | | | | | | | | | | | | | | | | | Year Ended December 31, 2016 | | West | | Texas | | East | | Consolidation and Elimination | | Total | Revenues from external customers | $ | 1,562 |
| | $ | 2,801 |
| | $ | 2,353 |
| | $ | — |
| | $ | 6,716 |
| Intersegment revenues | 7 |
| | 14 |
| | 11 |
| | (32 | ) | | — |
| Total operating revenues | $ | 1,569 |
| | $ | 2,815 |
| | $ | 2,364 |
| | $ | (32 | ) | | $ | 6,716 |
| Commodity Margin | $ | 991 |
| | $ | 655 |
| | $ | 958 |
| | $ | — |
| | $ | 2,604 |
| Add: Mark-to-market commodity activity, net and other(1) | (3 | ) | | (23 | ) | | (20 | ) | | (29 | ) | | (75 | ) | Less: | | | | | | | | | | Plant operating expense | 357 |
| | 317 |
| | 332 |
| | (29 | ) | | 977 |
| Depreciation and amortization expense | 225 |
| | 213 |
| | 224 |
| | — |
| | 662 |
| Sales, general and other administrative expense | 39 |
| | 56 |
| | 45 |
| | — |
| | 140 |
| Other operating expenses | 32 |
| | 9 |
| | 38 |
| | — |
| | 79 |
| Impairment losses | 13 |
| | — |
| | — |
| | — |
| | 13 |
| (Gain) on sale of assets, net | — |
| | — |
| | (157 | ) | | — |
| | (157 | ) | (Income) from unconsolidated subsidiaries | — |
| | — |
| | (24 | ) | | — |
| | (24 | ) | Income from operations | 322 |
| | 37 |
| | 480 |
| | — |
| | 839 |
| Interest expense | | | | | | | | | 631 |
| Debt modification and extinguishment costs and other (income) expense, net | | | | | | | | | 49 |
| Income before income taxes | | | | | | | | | $ | 159 |
|
| | | | | | | | | | | | | | | | | | | | | | Year Ended December 31, 2015 | | West | | Texas | | East | | Consolidation and Elimination | | Total | Revenues from external customers | $ | 2,089 |
| | $ | 2,344 |
| | $ | 2,039 |
| | $ | — |
| | $ | 6,472 |
| Intersegment revenues | 5 |
| | 15 |
| | 8 |
| | (28 | ) | | — |
| Total operating revenues | $ | 2,094 |
| | $ | 2,359 |
| | $ | 2,047 |
| | $ | (28 | ) | | $ | 6,472 |
| Commodity Margin | $ | 1,106 |
| | $ | 736 |
| | $ | 944 |
| | $ | — |
| | $ | 2,786 |
| Add: Mark-to-market commodity activity, net and other(1) | 160 |
| | (120 | ) | | (92 | ) | | (29 | ) | | (81 | ) | Less: | | | | | | | | | | Plant operating expense | 416 |
| | 338 |
| | 292 |
| | (28 | ) | | 1,018 |
| Depreciation and amortization expense | 250 |
| | 204 |
| | 184 |
| | — |
| | 638 |
| Sales, general and other administrative expense | 35 |
| | 63 |
| | 40 |
| | — |
| | 138 |
| Other operating expenses | 37 |
| | 9 |
| | 36 |
| | (2 | ) | | 80 |
| (Income) from unconsolidated subsidiaries | — |
| | — |
| | (24 | ) | | — |
| | (24 | ) | Income from operations | 528 |
| | 2 |
| | 324 |
| | 1 |
| | 855 |
| Interest expense | | | | | | | | | 628 |
| Debt modification and extinguishment costs and other (income) expense, net | | | | | | | | | 54 |
| Income before income taxes | | | | | | | | | $ | 173 |
|
| | | | | | | | | | | | | | | | | | | | | | Year Ended December 31, 2014 | | West | | Texas | | East | | Consolidation and Elimination | | Total | Revenues from external customers | $ | 2,352 |
| | $ | 3,229 |
| | $ | 2,449 |
| | $ | — |
| | $ | 8,030 |
| Intersegment revenues | 6 |
| | 23 |
| | 47 |
| | (76 | ) | | — |
| Total operating revenues | $ | 2,358 |
| | $ | 3,252 |
| | $ | 2,496 |
| | $ | (76 | ) | | $ | 8,030 |
| Commodity Margin(2) | $ | 1,050 |
| | $ | 760 |
| | $ | 949 |
| | $ | — |
| | $ | 2,759 |
| Add: Mark-to-market commodity activity, net and other(1) | 220 |
| | 142 |
| | 48 |
| | (31 | ) | | 379 |
| Less: | | | | | | | | | | Plant operating expense | 385 |
| | 313 |
| | 302 |
| | (31 | ) | | 969 |
| Depreciation and amortization expense | 245 |
| | 191 |
| | 168 |
| | (1 | ) | | 603 |
| Sales, general and other administrative expense | 41 |
| | 64 |
| | 39 |
| | — |
| | 144 |
| Other operating expenses | 50 |
| | 5 |
| | 32 |
| | 1 |
| | 88 |
| Impairment losses | — |
| | — |
| | 123 |
| | — |
| | 123 |
| (Gain) on sale of assets, net | — |
| | — |
| | (753 | ) | | — |
| | (753 | ) | (Income) from unconsolidated subsidiaries | — |
| | — |
| | (25 | ) | | — |
| | (25 | ) | Income from operations | 549 |
| | 329 |
| | 1,111 |
| | — |
| | 1,989 |
| Interest expense | | | | | | | | | 645 |
| Debt extinguishment costs and other (income) expense, net | | | | | | | | | 361 |
| Income before income taxes | | | | | | | | | $ | 983 |
|
__________ | | (1) | Includes $(2) million, $(2) million and $(5) million of lease levelization and $122 million, $20 million and $14 million of amortization expense for the years ended December 31, 2016, 2015 and 2014, respectively. |
| | (2) | Our East segment includes Commodity Margin of $81 million for the year ended December 31, 2014 related to the six power plants in our East segment that were sold in July 2014. |
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