<ARTICLE> 5 <MULTIPLIER> 1,000 <PERIOD-TYPE> 9-MOS <FISCAL-YEAR-END> DEC-31-1997 <PERIOD-END> SEP-30-1997 <CASH> 136,813 <SECURITIES> 507,732 <RECEIVABLES> 221,824 <ALLOWANCES> 3,749 <INVENTORY> 100,894 <CURRENT-ASSETS> 1,041,608 <PP&E> 1,634,099 <DEPRECIATION> 610,049 <TOTAL-ASSETS> 2,184,536 <CURRENT-LIABILITIES> 462,218 <BONDS> 0 <COMMON> 1,417 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <OTHER-SE> 1,581,926 <TOTAL-LIABILITY-AND-EQUITY> 2,184,536 <SALES> 967,239 <TOTAL-REVENUES> 967,239 <CGS> 496,848 <TOTAL-COSTS> 496,848 <OTHER-EXPENSES> 312,416 <LOSS-PROVISION> 0 <INTEREST-EXPENSE> 0 <INCOME-PRETAX> 178,697 <INCOME-TAX> 50,173 <INCOME-CONTINUING> 128,524 <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> 128,524 <EPS-PRIMARY> 0.91 <EPS-DILUTED> 0.90