<TABLE> <S> <C>

<PAGE>

<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM FORM 10
QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITY EXCHANGE ACT OF
1934 FOR THE QUARTERLY PERIOD ENDED JUNE 30, 2000 AND IS QUALIFIED IN ITS
ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000

<S>                             <C>                     <C>
<PERIOD-TYPE>                   3-MOS                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-2000             DEC-31-2000
<PERIOD-START>                             APR-01-2000             JAN-01-2000
<PERIOD-END>                               JUN-30-2000             JUN-30-2000
<CASH>                                           8,186                   8,186
<SECURITIES>                                         0                       0
<RECEIVABLES>                                    6,139                   6,139
<ALLOWANCES>                                      (13)                    (13)
<INVENTORY>                                          0                       0
<CURRENT-ASSETS>                                14,441                  14,441
<PP&E>                                         238,317                 238,317
<DEPRECIATION>                               (164,709)               (164,709)
<TOTAL-ASSETS>                                 101,114                  101,14
<CURRENT-LIABILITIES>                           11,866                  11,866
<BONDS>                                              0                       0
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                            87                      87
<OTHER-SE>                                      45,511                  45,511
<TOTAL-LIABILITY-AND-EQUITY>                   101,114                 101,114
<SALES>                                          8,746                  15,891
<TOTAL-REVENUES>                                 9,203                  16,903
<CGS>                                                0                       0
<TOTAL-COSTS>                                    4,363                   8,669
<OTHER-EXPENSES>                                     0                       0
<LOSS-PROVISION>                                     0                       0
<INTEREST-EXPENSE>                                 992                   2,018
<INCOME-PRETAX>                                  4,220                   6,781
<INCOME-TAX>                                     1,648                   2,699
<INCOME-CONTINUING>                              2,572                   4,082
<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                    242                     242
<CHANGES>                                            0                       0
<NET-INCOME>                                     2,330                   3,840
<EPS-BASIC>                                       0.27                    0.44
<EPS-DILUTED>                                     0.27                    0.44


</TABLE>