<TABLE> <S> <C>

<PAGE>

<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE BALANCE
SHEETS OF THE COMPANY AS OF MARCH 31, 2000 (UNAUDITED) AND DECEMBER 31, 1999,
STATEMENTS OF INCOME FOR THE PERIODS ENDED MARCH 31, 2000 AND 1999 (UNAUDITED)
AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>

<S>                             <C>                     <C>
<PERIOD-TYPE>                   3-MOS                   3-MOS
<FISCAL-YEAR-END>                          DEC-31-2000             DEC-31-1999
<PERIOD-START>                              JAN-1-2000              JAN-1-1999
<PERIOD-END>                               MAR-31-2000             MAR-31-1999
<CASH>                                          12,210                  13,313
<SECURITIES>                                         0                       0
<RECEIVABLES>                                   33,130                  31,167
<ALLOWANCES>                                     2,634                   2,890
<INVENTORY>                                          0                       0
<CURRENT-ASSETS>                                     0                       0
<PP&E>                                       1,913,562               1,898,482
<DEPRECIATION>                                 101,637                  91,461
<TOTAL-ASSETS>                               2,009,537               1,994,663
<CURRENT-LIABILITIES>                                0                       0
<BONDS>                                              0                       0
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                    100,000                 100,000
<COMMON>                                           402                     401
<OTHER-SE>                                     702,037                 731,092
<TOTAL-LIABILITY-AND-EQUITY>                 2,009,537               1,994,663
<SALES>                                              0                       0
<TOTAL-REVENUES>                                81,113                  71,392
<CGS>                                                0                       0
<TOTAL-COSTS>                                   62,257                  52,653
<OTHER-EXPENSES>                                     0                       0
<LOSS-PROVISION>                                     0                       0
<INTEREST-EXPENSE>                              17,026                  13,494
<INCOME-PRETAX>                                 16,947                  17,257
<INCOME-TAX>                                         0                       0
<INCOME-CONTINUING>                                  0                       0
<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                    16,947                  17,257
<EPS-BASIC>                                        .42                     .41
<EPS-DILUTED>                                      .42                     .41


</TABLE>