<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
STATEMENT OF INCOME FOR THE NINE MONTHS ENDED SEPTEMBER 30,1998 AND THE BALANCE
SHEET AT SEPTEMBER 30, 1998 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO
SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1998
<PERIOD-START>                             JAN-01-1998
<PERIOD-END>                               SEP-30-1998
<CASH>                                           1,057
<SECURITIES>                                         0
<RECEIVABLES>                                  154,116
<ALLOWANCES>                                     8,379
<INVENTORY>                                      1,277
<CURRENT-ASSETS>                               177,556
<PP&E>                                       1,748,030
<DEPRECIATION>                                 921,682
<TOTAL-ASSETS>                               1,013,282
<CURRENT-LIABILITIES>                          277,077
<BONDS>                                        168,185
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                       191,968
<OTHER-SE>                                     188,500
<TOTAL-LIABILITY-AND-EQUITY>                 1,013,282
<SALES>                                              0
<TOTAL-REVENUES>                               476,850
<CGS>                                                0
<TOTAL-COSTS>                                  351,941
<OTHER-EXPENSES>                                     0
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                              12,884
<INCOME-PRETAX>                                126,459
<INCOME-TAX>                                    52,073
<INCOME-CONTINUING>                             74,386
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                  (983)
<CHANGES>                                            0
<NET-INCOME>                                    73,403
<EPS-PRIMARY>                                        0
<EPS-DILUTED>                                        0