<ARTICLE> 5 <MULTIPLIER> 1,000 <PERIOD-TYPE> 3-MOS <FISCAL-YEAR-END> DEC-31-1999 <PERIOD-START> JAN-01-1999 <PERIOD-END> MAR-31-1999 <CASH> 177,850 <SECURITIES> 36,394 <RECEIVABLES> 136,995 <ALLOWANCES> 0 <INVENTORY> 10,449 <CURRENT-ASSETS> 505,076 <PP&E> 767,112 <DEPRECIATION> 429,362 <TOTAL-ASSETS> 1,102,127 <CURRENT-LIABILITIES> 372,147 <BONDS> 105,486 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <COMMON> 79,415 <OTHER-SE> 509,899 <TOTAL-LIABILITY-AND-EQUITY> 1,102,127 <SALES> 414,077 <TOTAL-REVENUES> 414,077 <CGS> 180,485 <TOTAL-COSTS> 336,430 <OTHER-EXPENSES> (1,604) <LOSS-PROVISION> 0 <INTEREST-EXPENSE> 1,782 <INCOME-PRETAX> 77,469 <INCOME-TAX> 29,856 <INCOME-CONTINUING> 47,613 <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> 47,613 <EPS-PRIMARY> .60 <EPS-DILUTED> .59