<ARTICLE>                                     5
<MULTIPLIER>                                             1,000
<CURRENCY>                                    U.S. DOLLARS

                                           
<PERIOD-TYPE>                                 9-MOS
<FISCAL-YEAR-END>                             DEC-31-2000
<PERIOD-START>                                JAN-01-2000
<PERIOD-END>                                  SEP-30-2000
<EXCHANGE-RATE>                                              1
<CASH>                                                   6,571
<SECURITIES>                                                 0
<RECEIVABLES>                                           53,185
<ALLOWANCES>                                                 0
<INVENTORY>                                                  0
<CURRENT-ASSETS>                                        64,208
<PP&E>                                                 377,875
<DEPRECIATION>                                         169,994
<TOTAL-ASSETS>                                         281,683
<CURRENT-LIABILITIES>                                   23,560
<BONDS>                                                  3,000
<PREFERRED-MANDATORY>                                        0
<PREFERRED>                                                  0
<COMMON>                                                   284
<OTHER-SE>                                             232,310
<TOTAL-LIABILITY-AND-EQUITY>                           281,683
<SALES>                                                133,604
<TOTAL-REVENUES>                                       137,253
<CGS>                                                   26,061
<TOTAL-COSTS>                                           73,054
<OTHER-EXPENSES>                                         1,178
<LOSS-PROVISION>                                             0
<INTEREST-EXPENSE>                                         148
<INCOME-PRETAX>                                         64,706
<INCOME-TAX>                                            25,084
<INCOME-CONTINUING>                                     39,622
<DISCONTINUED>                                               0
<EXTRAORDINARY>                                              0
<CHANGES>                                                    0
<NET-INCOME>                                            39,622
<EPS-BASIC>                                               1.43
<EPS-DILUTED>                                             1.41