WESTERN GAS RESOURCES, INC.  COMPUTATION OF PER SHARE EARNINGS  DECEMBER 31, 2001

|                                                                          |                                                                    | Weighted
Average
Shares Of
Common
Stock
Outstanding |  | Net
Income |            | Earnings
Per Share
Of Common
Stock
|------------------------------------------------------------------------- | ------------------------------------------------------------------ | --------------------------------------------------- |  | ---------- | ---------- | ----------------------------------
|Net income                                                                |                                                                    |                                                     |  | $          | 95,637,000 |                                   
|Weighted average shares of common stock outstanding                       |                                                                    | 32,579,813                                          |  |            |            |                                   
|Less preferred stock dividends:                                           |                                                                    |                                                     |  |            |            |                                   
|                                                                          | $2.28 cumulative preferred stock                                   |                                                     |  |            |            | (3,009,722                        
|                                                                          | Special dividend on redemption of $2.28 cumulative preferred stock |                                                     |  |            |            | (912,000                          
|                                                                          | $2.625 cumulative convertible preferred stock                      |                                                     |  |            |            | (7,245,000                        
|                                                                          |                                                                    |                                                     |  |            |            |                                   
|                                                                          |                                                                    | 32,579,813                                          |  | $          | 84,470,278 |                                   
|                                                                          |                                                                    |                                                     |  |            |            |                                   
|Basic earnings per share of common stock                                  |                                                                    |                                                     |  |            |            |                                   
|                                                                          |                                                                    |                                                     |  |            |            |                                   
|Assume conversion of $2.625 convertible preferred stock                   |                                                                    | 3,471,698                                           |  |            | 7,245,000  |                                   
|Assume exercise of common stock equivalents                               |                                                                    | 970,858                                             |  |            |            |                                   
|(Anti-dilutive common stock equivalents are not used in this calculation) |                                                                    | 37,022,369                                          |  | $          | 91,715,278 |                                   
|                                                                          |                                                                    |                                                     |  |            |            |                                   
|Fully diluted earnings per share of common stock                          |                                                                    |                                                     |  |            |            |                                   
|                                                                          |                                                                    |                                                     |  |            |            |                                   



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