
<TABLE> <S> <C>

<ARTICLE> 5
<MULTIPLIER> 1000
       
<S>                             <C>
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               SEP-30-1997
<CASH>                                         162,386
<SECURITIES>                                         0
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<ALLOWANCES>                                         0
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<CURRENT-ASSETS>                               447,340
<PP&E>                                         442,754
<DEPRECIATION>                                 279,342
<TOTAL-ASSETS>                                 984,423
<CURRENT-LIABILITIES>                          385,197
<BONDS>                                              0
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                           576
<OTHER-SE>                                     465,697
<TOTAL-LIABILITY-AND-EQUITY>                   984,423
<SALES>                                              0
<TOTAL-REVENUES>                             1,027,963
<CGS>                                                0
<TOTAL-COSTS>                                  995,341
<OTHER-EXPENSES>                                 (278)
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                             (3,348)
<INCOME-PRETAX>                                 36,248
<INCOME-TAX>                                    16,384
<INCOME-CONTINUING>                             19,864
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                    19,864
<EPS-PRIMARY>                                     0.34
<EPS-DILUTED>                                     0.34
        

</TABLE>
