<ARTICLE> 5 <LEGEND> THIS SCHEDULE CONTAINS SUMMARY INFORMATION EXTRACTED FROM THE CONSOLIDATED BALANCE SHEET AND THE CONSOLIDATED STATEMENT OF INCOME FILED AS PART OF THE ANNUAL REPORT ON FORM 10-Q AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH ANNUAL REPORT ON FORM 10-Q. </LEGEND> <MULTIPLIER> 1,000 <PERIOD-TYPE> 3-MOS <FISCAL-YEAR-END> DEC-31-1997 <PERIOD-END> MAR-31-1997 <CASH> $2,615 <SECURITIES> $0 <RECEIVABLES> $146,957 <ALLOWANCES> $1,359 <INVENTORY> $91,533 <CURRENT-ASSETS> $258,074 <PP&E> $1,152,283 <DEPRECIATION> $661,422 <TOTAL-ASSETS> $842,146 <CURRENT-LIABILITIES> $134,812 <BONDS> $0 <PREFERRED-MANDATORY> $0 <PREFERRED> $0 <COMMON> $550 <OTHER-SE> $509,686 <TOTAL-LIABILITY-AND-EQUITY> $842,146 <SALES> $198,394 <TOTAL-REVENUES> $198,394 <CGS> $132,032 <TOTAL-COSTS> $166,028 <OTHER-EXPENSES> $0 <LOSS-PROVISION> $0 <INTEREST-EXPENSE> $197 <INCOME-PRETAX> $32,231 <INCOME-TAX> $12,054 <INCOME-CONTINUING> $20,177 <DISCONTINUED> $0 <EXTRAORDINARY> $0 <CHANGES> $0 <NET-INCOME> $20,177 <EPS-PRIMARY> $0.36 <EPS-DILUTED> $0.36