<ARTICLE> 5 <MULTIPLIER> 1000 <PERIOD-TYPE> 12-MOS <FISCAL-YEAR-END> DEC-31-1997 <PERIOD-END> DEC-31-1997 <CASH> 205,726 <SECURITIES> 0 <RECEIVABLES> 260,821 <ALLOWANCES> 0 <INVENTORY> 0 <CURRENT-ASSETS> 504,970 <PP&E> 448,653 <DEPRECIATION> 282,993 <TOTAL-ASSETS> 1,039,108 <CURRENT-LIABILITIES> 469,114 <BONDS> 0 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <COMMON> 577 <OTHER-SE> 459,527 <TOTAL-LIABILITY-AND-EQUITY> 1,039,108 <SALES> 0 <TOTAL-REVENUES> 1,391,587 <CGS> 0 <TOTAL-COSTS> 1,366,831 <OTHER-EXPENSES> (38,537) <LOSS-PROVISION> 0 <INTEREST-EXPENSE> (5,251) <INCOME-PRETAX> 68,544 <INCOME-TAX> 32,647 <INCOME-CONTINUING> 35,897 <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> 35,897 <EPS-PRIMARY> 0.62 <EPS-DILUTED> 0.62