<TABLE> <S> <C>
<PAGE>
<ARTICLE> UT
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
STATEMENTS OF INCOME, BALANCE SHEETS, STATEMENTS OF CAPITALIZATION, STATEMENTS
OF CHANGES IN COMMON STOCKHOLDERS' EQUITY AND STATEMENTS OF CASH FLOWS AND IS
QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> DEC-31-1999
<PERIOD-END> DEC-31-1999
<BOOK-VALUE> PER-BOOK
<TOTAL-NET-UTILITY-PLANT> 10,145,284
<OTHER-PROPERTY-AND-INVEST> 4,606,678
<TOTAL-CURRENT-ASSETS> 2,060,944
<TOTAL-DEFERRED-CHARGES> 566,727
<OTHER-ASSETS> 690,725
<TOTAL-ASSETS> 18,070,358
<COMMON> 838,193
<CAPITAL-SURPLUS-PAID-IN> 2,288,254
<RETAINED-EARNINGS> 2,253,800
<TOTAL-COMMON-STOCKHOLDERS-EQ> 5,290,220<F1>
494,000
105,340
<LONG-TERM-DEBT-NET> 5,827,485
<SHORT-TERM-NOTES> 399,159
<LONG-TERM-NOTES-PAYABLE> 0
<COMMERCIAL-PAPER-OBLIGATIONS> 1,033,527
<LONG-TERM-DEBT-CURRENT-PORT> 431,049
0
<CAPITAL-LEASE-OBLIGATIONS> 56,645
<LEASES-CURRENT> 0
<OTHER-ITEMS-CAPITAL-AND-LIAB> 4,432,933<F1>
<TOT-CAPITALIZATION-AND-LIAB> 18,070,358
<GROSS-OPERATING-REVENUE> 6,869,404
<INCOME-TAX-EXPENSE> 179,673
<OTHER-OPERATING-EXPENSES> 5,646,847
<TOTAL-OPERATING-EXPENSES> 5,646,847
<OPERATING-INCOME-LOSS> 1,222,557
<OTHER-INCOME-NET> (18,874)
<INCOME-BEFORE-INTEREST-EXPEN> 1,024,010
<TOTAL-INTEREST-EXPENSE> 453,077
<NET-INCOME> 570,933
5,292
<EARNINGS-AVAILABLE-FOR-COMM> 565,641
<COMMON-STOCK-DIVIDENDS> 489,913
<TOTAL-INTEREST-ON-BONDS> 283,662
<CASH-FLOW-OPERATIONS> 1,325,429
<EPS-BASIC> 1.70
<EPS-DILUTED> 1.70
<FN>
<F1>Note 1 - ($90,027) thousand of Common Stockholders' Equity is classified as
Other Items-Capitalization and Liabilities. This represents the net of
leveraged common stock held by the Employee Stock Ownership Plan, currency
translation adjustments, and investment valuation reserve.
</FN>
</TABLE>
