<ARTICLE> 5 <MULTIPLIER> 1000 <PERIOD-TYPE> 6-MOS <FISCAL-YEAR-END> DEC-31-1997 <PERIOD-END> JUN-30-1997 <CASH> 1,412 <SECURITIES> 0 <RECEIVABLES> 4,861 <ALLOWANCES> 0 <INVENTORY> 241 <CURRENT-ASSETS> 7,735 <PP&E> 184,556 <DEPRECIATION> 59,218 <TOTAL-ASSETS> 249,815 <CURRENT-LIABILITIES> 8,094 <BONDS> 0 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <COMMON> 27,817 <OTHER-SE> 137,364 <TOTAL-LIABILITY-AND-EQUITY> 249,815 <SALES> 11,085 <TOTAL-REVENUES> 19,628 <CGS> 1,740 <TOTAL-COSTS> 1,740 <OTHER-EXPENSES> 8,664 <LOSS-PROVISION> 0 <INTEREST-EXPENSE> 1,114 <INCOME-PRETAX> 10,026 <INCOME-TAX> 2,155 <INCOME-CONTINUING> 7,871 <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> 7,871 <EPS-PRIMARY> 0.93 <EPS-DILUTED> 0.93