**Exhibit 11.1**

 

WESTERN GAS RESOURCES, INC.

COMPUTATION OF PER SHARE EARNINGS

DECEMBER 31, 2004

 
| ** **                                                                       | ** ** | **Weighted**    | ** ** | ** ** | ** **  | ** **    | ** ** |
|----------------------------------------------------------------------------------|------------|-----------------|------------|------------|-------------|---------------|------------|
| ** **                                                                       | ** ** | **Average**     | ** ** | ** ** | ** **  | ** **    | ** ** |
| ** **                                                                       | ** ** | **Shares Of**   | ** ** | ** ** | ** **  | **Earnings**  | ** ** |
|                                                                             |       | **Common**      |       |       |        | **Per Share** |       |
| ** **                                                                       | ** ** | **Stock**       | ** ** | **Net**    | ** **  | **Of Common** |       |
| ** **                                                                       | ** ** | **Outstanding** | ** ** | **Income** | ** **  | **Stock**     |       |
|                                                                             |       |            |       |       |        |          |       |
| Net income (Restated)                                                            |       |            |       | $          | 127,759,000 |          |       |   |
|                                                                             |       |            |       |       |        |          |       |
| Weighted average shares of  common stock outstanding                             |       | 72,419,980      |       |       |        |          |       |
|                                                                             |       |            |       |       |        |          |       |
| Less preferred stock dividends:                                                  |       |            |       |       |        |          |       |
| Special dividend on redemption  of $2.625 cumulative convertible preferred stock |       |            |       | (46,423    | )           |          |       |
| $ 2.625 cumulative convertible preferred  stock                             |       |            |       | (788,902   | )           |          |       |
|                                                                             |       |            |       |       |        |          |       |
|                                                                             |       | 72,419,980      |       | $          | 126,923,675 |          |       |   |
|                                                                             |       |            |       |       |        |          |       |
| Basic earnings per share of  common stock (Restated)                             |       |            |       |       |        | $             | 1.75       |   |
|                                                                             |       |            |       |       |        |          |       |
| Assume exercise of common  stock equivalents                                     |       | 1,074,767       |       | —     |        |          |       |
| (Anti-dilutive common stock  equivalents are not used in this calculation)       |       |            |       |       |        |          |       |
|                                                                             |       |            |       |       |        |          |       |
|                                                                             |       | 73,494,747      |       | $          | 126,923,675 |          |       |   |
|                                                                             |       |            |       |       |        |          |       |
| Fully diluted earnings per  share of common stock (Restated)                     |       |            |       |       |        | $             | 1.73       |   |

 

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