<TABLE> <S> <C>
<PAGE>
<ARTICLE> UT
<MULTIPLIER> 1,000
<S> <C>
<PERIOD-TYPE> 9-MOS
<FISCAL-YEAR-END> DEC-31-2000
<PERIOD-START> JAN-01-2000
<PERIOD-END> SEP-30-2000
<BOOK-VALUE> PER-BOOK
<TOTAL-NET-UTILITY-PLANT> 1,325,886
<OTHER-PROPERTY-AND-INVEST> 1,118,646
<TOTAL-CURRENT-ASSETS> 365,911
<TOTAL-DEFERRED-CHARGES> 1,021,978
<OTHER-ASSETS> 0
<TOTAL-ASSETS> 3,832,421
<COMMON> 73,119
<CAPITAL-SURPLUS-PAID-IN> 959,269
<RETAINED-EARNINGS> 1,002,316
<TOTAL-COMMON-STOCKHOLDERS-EQ> 846,420<F1>
0
246,723<F2>
<LONG-TERM-DEBT-NET> 1,373,626
<SHORT-TERM-NOTES> 0
<LONG-TERM-NOTES-PAYABLE> 2,543
<COMMERCIAL-PAPER-OBLIGATIONS> 0
<LONG-TERM-DEBT-CURRENT-PORT> 128,134
0
<CAPITAL-LEASE-OBLIGATIONS> 10,976
<LEASES-CURRENT> 776
<OTHER-ITEMS-CAPITAL-AND-LIAB> 1,223,223
<TOT-CAPITALIZATION-AND-LIAB> 3,832,421
<GROSS-OPERATING-REVENUE> 1,010,103
<INCOME-TAX-EXPENSE> 70,418<F3>
<OTHER-OPERATING-EXPENSES> 932,289
<TOTAL-OPERATING-EXPENSES> 932,289
<OPERATING-INCOME-LOSS> 77,814
<OTHER-INCOME-NET> 211,881
<INCOME-BEFORE-INTEREST-EXPEN> 289,695
<TOTAL-INTEREST-EXPENSE> 94,233<F4>
<NET-INCOME> 125,044
(427)
<EARNINGS-AVAILABLE-FOR-COMM> 125,471
<COMMON-STOCK-DIVIDENDS> 76,513
<TOTAL-INTEREST-ON-BONDS> 56,203
<CASH-FLOW-OPERATIONS> 271,796
<EPS-BASIC> 1.91
<EPS-DILUTED> 1.87
<FN>
<F1>Includes $(1,188,284) of Treasury Stock at cost
<F2>Includes $12,019 of Preference Stock
<F3>Non-Operating Expense
<F4>Includes $11,991 of Preferred and Preference Stock Dividends
</FN>
</TABLE>
