<ARTICLE> 5 <MULTIPLIER> 1,000 <PERIOD-TYPE> 6-MOS <FISCAL-YEAR-END> Dec-31-2000 <PERIOD-END> Jun-30-2000 <CASH> 84,839 <SECURITIES> 0 <RECEIVABLES> 198,344 <ALLOWANCES> 0 <INVENTORY> 29,566 <CURRENT-ASSETS> 336,540 <PP&E> 4,548,601 <DEPRECIATION> 2,339,617 <TOTAL-ASSETS> 2,777,042 <CURRENT-LIABILITIES> 350,491 <BONDS> 1,257,268 <PREFERRED-MANDATORY> 0 <PREFERRED> 50 <COMMON> 16,864 <OTHER-SE> 1,013,686 <TOTAL-LIABILITY-AND-EQUITY> 2,777,042 <SALES> 482,497 <TOTAL-REVENUES> 482,497 <CGS> 0 <TOTAL-COSTS> 267,742 <OTHER-EXPENSES> 2,441 <LOSS-PROVISION> 0 <INTEREST-EXPENSE> 38,094 <INCOME-PRETAX> 159,148 <INCOME-TAX> 70,677 <INCOME-CONTINUING> 88,471 <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> 88,471 <EPS-BASIC> 0.52 <EPS-DILUTED> 0.50