<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
CONDENSED STATEMENT OF INCOME FOR THE SIX MONTHS ENDED JUNE 30, 2000 AND THE
CONDENSED BALANCE SHEET AT JUNE 30, 2000 AND IS QUALIFIED IN ITS ENTIRETY BY
REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000

                             
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-2000
<PERIOD-START>                             JAN-01-2000
<PERIOD-END>                               JUN-30-2000
<CASH>                                           2,467
<SECURITIES>                                         0
<RECEIVABLES>                                  151,031
<ALLOWANCES>                                     9,824
<INVENTORY>                                        794
<CURRENT-ASSETS>                               179,196
<PP&E>                                       1,949,995
<DEPRECIATION>                               1,052,881
<TOTAL-ASSETS>                               1,100,815
<CURRENT-LIABILITIES>                          307,464
<BONDS>                                        164,325
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                       191,968
<OTHER-SE>                                     232,273
<TOTAL-LIABILITY-AND-EQUITY>                 1,100,815
<SALES>                                              0
<TOTAL-REVENUES>                               347,734
<CGS>                                                0
<TOTAL-COSTS>                                  259,584
<OTHER-EXPENSES>                                     0
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                               7,591
<INCOME-PRETAX>                                 81,936
<INCOME-TAX>                                    35,870
<INCOME-CONTINUING>                             46,066
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                    46,066
<EPS-BASIC>                                          0
<EPS-DILUTED>                                        0