<ARTICLE> 5
<LEGEND> THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
MARCH 31, 1998 CONSOLIDATED BALANCE SHEET AND THE CONSOLIDATED STATEMENT OF
INCOME FOR THE THREE-MONTH PERIOD ENDED MARCH 31, 1998, AND IS QUALIFIED IN ITS
ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS AND THE FOOTNOTES THERETO.
</LEGEND>
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   3-MOS
<FISCAL-YEAR-END>                         DEC-31-1998
<PERIOD-START>                            JAN-01-1998
<PERIOD-END>                              MAR-31-1998
<CASH>                                        311,861
<SECURITIES>                                    3,053         
<RECEIVABLES>                               1,517,915
<ALLOWANCES>                                   54,161
<INVENTORY>                                         0
<CURRENT-ASSETS>                            2,179,626 
<PP&E>                                     11,793,089
<DEPRECIATION>                              4,666,663
<TOTAL-ASSETS>                             13,864,000
<CURRENT-LIABILITIES>                       4,509,073
<BONDS>                                     5,398,132
<PREFERRED-MANDATORY>                               0
<PREFERRED>                                         0
<COMMON>                                      507,102
<OTHER-SE>                                    847,791
<TOTAL-LIABILITY-AND-EQUITY>               13,864,000
<SALES>                                             0 
<TOTAL-REVENUES>                            2,131,621
<CGS>                                               0         
<TOTAL-COSTS>                               1,621,985 
<OTHER-EXPENSES>                                    0
<LOSS-PROVISION>                                7,243
<INTEREST-EXPENSE>                            115,574
<INCOME-PRETAX>                               170,968
<INCOME-TAX>                                   96,551
<INCOME-CONTINUING>                            74,417
<DISCONTINUED>                                      0 
<EXTRAORDINARY>                                     0
<CHANGES>                                           0 
<NET-INCOME>                                   74,417
<EPS-PRIMARY>                                    0.16
<EPS-DILUTED>                                    0.16