Exhibit 99.1 NISOURCE INC. UNAUDITED PRO FORMA COMBINED CONDENSED STATEMENT OF INCOME FROM CONTINUING OPERATIONS FOR TWELVE MONTHS ENDED DECEMBER 31, 2000 NiSource Columbia 12 Mos Ended 10 Mos Ended Pro Forma (IN MILLIONS, EXCEPT PER SHARE AMOUNTS) 12/31/2000 10/31/2000 Adjustments Combined ------------ ------------ ----------- --------- NET REVENUES $1,948.0 $1,504.5 $ - $ 3,452.5 OPERATING EXPENSES Operation and maintenance 801.7 962.1 (336.5)A 1,427.3 Depreciation, amortization and depletion 374.1 168.1 83.8B 626.0 Loss on asset impairment 65.8 65.8 Other taxes 138.6 156.3 294.9 ------- ------- ------- Total Operating Expenses 1,380.2 1,286.5 (252.7) 2,414.0 ------- ------- ------- ------- OPERATING INCOME 567.8 218.0 252.7 1,038.5 ------- ------- ------ ------- OTHER INCOME (DEDUCTIONS) Interest expenses, net (304.5) (135.4) (227.0)C (666.9) Minority interests (20.4) (20.4) Preferred stock dividends of subsidiaries (7.8) (7.8) Other, net 42.1 126.7 168.8 Total Other Income (Deductions) (290.6) (8.7) (227.0) (526.3) ------ ------- ------- ------- INCOME FROM CONTINUING OPERATIONS BEFORE INCOME 277.2 209.3 25.7 512.2 TAXES INCOME TAXES 130.1 91.2 38.1D 259.4 INCOME FROM CONTINUING OPERATIONS $147.1 $118.1 $(12.4) $252.8 ------ -------- ------ ------- BASIC EARNINGS PER SHARE - CONTINUING OPERATIONS $ 1.09 $ 1.30 ------ ------- DILUTED EARNINGS PER SHARE - CONTINUING OPERATIONS $ 1.08 $ 1.29 ------ ------- AVERAGE COMMON SHARES OUTSTANDING (THOUSANDS) 134,470 60,378E 194,848 DILUTED AVERAGE COMMON SHARES (THOUSANDS) 135,811 60,378E 196,189 -------- ------- -------- SEE NOTES TO UNAUDITED PRO FORMA COMBINED CONDENSED STATEMENT OF INCOME. NOTES TO UNAUDITED PRO FORMA COMBINED CONDENSED STATEMENT OF INCOME A. To reflect the elimination of acquisition related retention and change in control costs, as well as, other non-recurring items related to the acquisition. B. To adjust historical depreciation, depletion and amortization expense to recognize goodwill amortization and depletion for a twelve month period. The amortization of goodwill reflects a straight-line amortization over a 40 year period. Depletion of oil and gas properties is based on actual depletion recorded by NiSource in November and December of 2000. C. To adjust interest expense to reflect the cost of the increased indebtedness from completion of the acquisition with an effective date of January 1, 2000. The pro forma statements assume a weighted average 7.5% per annum interest rate on the indebtedness incurred to complete the acquisition. A one-eighth percent variance from the assumed rate increases or decreases pre-tax interest expense by approximately $4.6 million on an annual basis. D. To recognize the estimated pro forma income tax effect of the decrease in O&M reflected in adjustment (A), the increase in property depletion reflected in adjustment (B) and the increase in interest expense reflected in adjustment (C). E. To reflect the issuance of 3.04414 shares of NiSource common stock for each converted stock of Columbia common stock. This issuance resulted in 72.4 million additional outstanding shares. The Pro Forma EPS calculation assumes these shares were issued on January 1, 2000.