<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION
EXTRACTED FROM CONDENSED CONSOLIDATED BALANCE SHEETS,
CONDENSED CONSOLIDATED STATEMENTS OF INCOME, AND NOTES
TO THE CONDENSED CONSOLIDATED FINANCIAL STATEMENTS AND
IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FORM
10-Q, SEPTEMBER  30, 1997.
</LEGEND>
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-START>                             JAN-01-1997
<PERIOD-END>                               SEP-30-1997
<CASH>                                          39,979
<SECURITIES>                                    18,154
<RECEIVABLES>                                  190,803
<ALLOWANCES>                                     1,061
<INVENTORY>                                     13,793
<CURRENT-ASSETS>                               327,461
<PP&E>                                         490,858
<DEPRECIATION>                                 297,329
<TOTAL-ASSETS>                                 564,869
<CURRENT-LIABILITIES>                          218,438
<BONDS>                                         70,114
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                           184
<OTHER-SE>                                     251,558
<TOTAL-LIABILITY-AND-EQUITY>                   564,869
<SALES>                                        718,385
<TOTAL-REVENUES>                               718,385
<CGS>                                          632,663
<TOTAL-COSTS>                                  687,296
<OTHER-EXPENSES>                                     0
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                               5,124
<INCOME-PRETAX>                                 35,240
<INCOME-TAX>                                    13,039
<INCOME-CONTINUING>                             22,201
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                    22,201
<EPS-PRIMARY>                                     1.21
<EPS-DILUTED>                                     1.21