<ARTICLE> 5
<MULTIPLIER> 1,000

                                                      
<PERIOD-TYPE>                   3-MOS                       6-MOS
<FISCAL-YEAR-END>                          DEC-31-1999                 DEC-31-1999
<PERIOD-START>                             APR-01-1999                 JAN-01-1999
<PERIOD-END>                               JUN-30-1999                 JUN-30-1999
<CASH>                                          44,900                      44,900
<SECURITIES>                                         0                           0
<RECEIVABLES>                                  249,600                     249,600
<ALLOWANCES>                                    15,300                      15,300
<INVENTORY>                                          0                           0
<CURRENT-ASSETS>                               325,800                     325,800
<PP&E>                                       2,046,600                   2,046,600
<DEPRECIATION>                                 520,500                     520,500
<TOTAL-ASSETS>                               3,102,100                   3,102,100
<CURRENT-LIABILITIES>                          348,400                     348,400
<BONDS>                                      1,118,500                   1,118,500
<PREFERRED-MANDATORY>                                0                           0
<PREFERRED>                                          0                           0
<COMMON>                                         1,800                       1,800
<OTHER-SE>                                   1,397,200                   1,397,200
<TOTAL-LIABILITY-AND-EQUITY>                 3,102,100                   3,102,100
<SALES>                                              0                           0
<TOTAL-REVENUES>                               455,600                     859,100
<CGS>                                                0                           0
<TOTAL-COSTS>                                  270,100                     514,800
<OTHER-EXPENSES>                                82,900                     162,300
<LOSS-PROVISION>                                     0                           0
<INTEREST-EXPENSE>                              14,400                      25,700
<INCOME-PRETAX>                                 88,600                     159,200
<INCOME-TAX>                                    34,100                      61,300
<INCOME-CONTINUING>                             54,500                      97,900
<DISCONTINUED>                                       0                           0
<EXTRAORDINARY>                                      0                           0
<CHANGES>                                            0                           0
<NET-INCOME>                                    54,500                      97,900
<EPS-BASIC>                                        .31                         .56
<EPS-DILUTED>                                      .31                         .56