
<TABLE> <S> <C>

<ARTICLE> 5
<MULTIPLIER> 1,000
       
<S>                             <C>
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>               DEC-31-1998
<PERIOD-START>                  JAN-01-1998
<PERIOD-END>                    SEP-30-1998
<CASH>                                14,088
<SECURITIES>                               0
<RECEIVABLES>                        326,579
<ALLOWANCES>                           9,990
<INVENTORY>                           38,960
<CURRENT-ASSETS>                     412,373
<PP&E>                             1,990,131
<DEPRECIATION>                     1,014,024
<TOTAL-ASSETS>                     1,425,065
<CURRENT-LIABILITIES>                303,969
<BONDS>                              250,289
<PREFERRED-MANDATORY>                      0
<PREFERRED>                                0
<COMMON>                              50,784
<OTHER-SE>                           681,134
<TOTAL-LIABILITY-AND-EQUITY>       1,425,065
<SALES>                                    0
<TOTAL-REVENUES>                   2,283,412
<CGS>                                      0
<TOTAL-COSTS>                      2,111,904
<OTHER-EXPENSES>                           0
<LOSS-PROVISION>                           0
<INTEREST-EXPENSE>                     9,881
<INCOME-PRETAX>                      161,627
<INCOME-TAX>                          62,627
<INCOME-CONTINUING>                   99,000
<DISCONTINUED>                             0
<EXTRAORDINARY>                            0
<CHANGES>                                  0
<NET-INCOME>                          99,000
<EPS-PRIMARY>                           1.98<F1>
<EPS-DILUTED>                           1.94<F2>
<FN>
<F1>EARNINGS PER SHARE - BASIC 
<F2>EARNINGS PER SHARE - DILUTED 
</FN>
        


</TABLE>
