<ARTICLE> UT <MULTIPLIER> 1,000 <PERIOD-TYPE> 9-MOS <FISCAL-YEAR-END> DEC-31-1997 <PERIOD-END> SEP-30-1997 <BOOK-VALUE> PER-BOOK <TOTAL-NET-UTILITY-PLANT> 2223400 <OTHER-PROPERTY-AND-INVEST> 0 <TOTAL-CURRENT-ASSETS> 313700 <TOTAL-DEFERRED-CHARGES> 336100 <OTHER-ASSETS> 278100 <TOTAL-ASSETS> 3151300 <COMMON> 400 <CAPITAL-SURPLUS-PAID-IN> 739000 <RETAINED-EARNINGS> 505200 <TOTAL-COMMON-STOCKHOLDERS-EQ> 1244600 <PREFERRED-MANDATORY> 0 <PREFERRED> 22900 <LONG-TERM-DEBT-NET> 925900 <SHORT-TERM-NOTES> 1300 <LONG-TERM-NOTES-PAYABLE> 0 <COMMERCIAL-PAPER-OBLIGATIONS> 6000 <LONG-TERM-DEBT-CURRENT-PORT> 400 <PREFERRED-STOCK-CURRENT> 0 <CAPITAL-LEASE-OBLIGATIONS> 0 <LEASES-CURRENT> 0 <OTHER-ITEMS-CAPITAL-AND-LIAB> 950200 <TOT-CAPITALIZATION-AND-LIAB> 3151300 <GROSS-OPERATING-REVENUE> 911000 <INCOME-TAX-EXPENSE> 79600 <OTHER-OPERATING-EXPENSES> 633700 <TOTAL-OPERATING-EXPENSES> 713300 <OPERATING-INCOME-LOSS> 197700 <OTHER-INCOME-NET> 6100 <INCOME-BEFORE-INTEREST-EXPEN> 203800 <TOTAL-INTEREST-EXPENSE> 64000 <NET-INCOME> 139800 <PREFERRED-STOCK-DIVIDENDS> 700 <EARNINGS-AVAILABLE-FOR-COMM> 139100 <COMMON-STOCK-DIVIDENDS> 86900 <TOTAL-INTEREST-ON-BONDS> 68600 <CASH-FLOW-OPERATIONS> 248800 <EPS-PRIMARY> 3.38 <EPS-DILUTED> 3.38