<ARTICLE> 5

                                                                       
<PERIOD-TYPE>                   3-MOS                   6-MOS                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1999             DEC-31-1999             DEC-31-1999
<PERIOD-START>                             JAN-01-1999             APR-01-1999             JUL-01-1999
<PERIOD-END>                               MAR-31-1999             JUN-30-1999             SEP-30-1999
<CASH>                                             663                     645                     618
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<INVENTORY>                                          0                       0                       0
<CURRENT-ASSETS>                                67,487                  64,184                  69,867
<PP&E>                                         255,549                 266,214                 273,850
<DEPRECIATION>                               (101,519)               (107,122)               (110,572)
<TOTAL-ASSETS>                                 235,933                 237,746                 247,760
<CURRENT-LIABILITIES>                           48,762                  57,185                  63,373
<BONDS>                                              0                       0                       0
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<PREFERRED>                                          0                       0                       0
<COMMON>                                           831                     831                     831
<OTHER-SE>                                      98,275                 102,539                 106,758
<TOTAL-LIABILITY-AND-EQUITY>                   235,933                 237,746                 247,780
<SALES>                                         99,346                 106,195                 108,527
<TOTAL-REVENUES>                                99,346                 106,195                 108,527
<CGS>                                                0                       0                       0
<TOTAL-COSTS>                                   93,858                  98,492                 100,670
<OTHER-EXPENSES>                                   245                     (4)                    (35)
<LOSS-PROVISION>                                     0                       0                       0
<INTEREST-EXPENSE>                               1,261                     829                   1,087
<INCOME-PRETAX>                                  3,982                   6,878                   6,805
<INCOME-TAX>                                     1,513                   2,614                   2,586
<INCOME-CONTINUING>                              2,469                   4,264                   4,219
<DISCONTINUED>                                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0
<CHANGES>                                            0                       0                       0
<NET-INCOME>                                     2,469                   4,264                   4,219
<EPS-BASIC>                                       0.30                     .51                     .51
<EPS-DILUTED>                                     0.30                     .51                     .51