<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY INFORMATION EXTRACTED FROM THE CONSOLIDATED
BALANCE SHEET AND CONSOLIDATED STATEMENT OF INCOME FILED AS PART OF THE
QUARTERLY REPORT ON FORM 10-Q AND IS QUALIFIED IN ITS ENTIRETY BY SUCH
QUARTERLY REPORT ON FORM 10-Q.
</LEGEND>
<MULTIPLIER> 1,000

                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1999
<PERIOD-END>                               SEP-30-1999
<CASH>                                         $45,655
<SECURITIES>                                        $0
<RECEIVABLES>                                 $144,069
<ALLOWANCES>                                    $2,971
<INVENTORY>                                   $116,797
<CURRENT-ASSETS>                              $321,151
<PP&E>                                      $1,285,942
<DEPRECIATION>                                $780,642
<TOTAL-ASSETS>                                $949,334
<CURRENT-LIABILITIES>                         $137,620
<BONDS>                                             $0
<PREFERRED-MANDATORY>                               $0
<PREFERRED>                                         $0
<COMMON>                                          $469
<OTHER-SE>                                    $487,516
<TOTAL-LIABILITY-AND-EQUITY>                  $949,334
<SALES>                                       $621,242
<TOTAL-REVENUES>                              $621,242
<CGS>                                         $427,250
<TOTAL-COSTS>                                 $541,896
<OTHER-EXPENSES>                                    $0
<LOSS-PROVISION>                                    $0
<INTEREST-EXPENSE>                              $6,883
<INCOME-PRETAX>                                $95,477
<INCOME-TAX>                                   $30,553
<INCOME-CONTINUING>                            $64,924
<DISCONTINUED>                                      $0
<EXTRAORDINARY>                                     $0
<CHANGES>                                           $0
<NET-INCOME>                                   $64,924
<EPS-BASIC>                                      $1.38
<EPS-DILUTED>                                    $1.36