<ARTICLE> 5 <MULTIPLIER> 1,000 <PERIOD-TYPE> 6-MOS <FISCAL-YEAR-END> DEC-31-1999 <PERIOD-START> JAN-01-1999 <PERIOD-END> JUN-30-1999 <CASH> 37,517 <SECURITIES> 90,045 <RECEIVABLES> 131,777 <ALLOWANCES> 1,987 <INVENTORY> 4,106 <CURRENT-ASSETS> 281,704 <PP&E> 213,346 <DEPRECIATION> 112,018 <TOTAL-ASSETS> 703,330 <CURRENT-LIABILITIES> 108,515 <BONDS> 0 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <COMMON> 76,256 <OTHER-SE> 491,013 <TOTAL-LIABILITY-AND-EQUITY> 703,330 <SALES> 385,161 <TOTAL-REVENUES> 385,161 <CGS> 283,553 <TOTAL-COSTS> 330,619 <OTHER-EXPENSES> (3,492) <LOSS-PROVISION> 0 <INTEREST-EXPENSE> 90 <INCOME-PRETAX> 57,944 <INCOME-TAX> 23,842 <INCOME-CONTINUING> 34,102 <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> 34,102 <EPS-BASIC> .48 <EPS-DILUTED> .47