NISOURCE INC

Presentation of Segment Information

In response to the NIPSCO Minority Interest Transaction, our operations are now evaluated through two primary reportable segments, Columbia Operations and NIPSCO Operations. Our historical segment disclosures have been recast to be consistent with the current presentation. Columbia Operations aggregates the results of the fully regulated and wholly owned subsidiaries of NiSource Gas Distribution Group, Inc. Each Columbia distribution company is an operating segment which we aggregate to form the Columbia Operations reportable segment. NIPSCO Operations aggregates the results of NIPSCO Holdings I, and its majority-owned subsidiaries, including NIPSCO, which has both fully regulated gas and electric operations in northern Indiana. The remainder of our operations, which are not significant enough on a stand-alone basis to warrant treatment as a reportable segment, are presented as "Corporate and Other" within the Notes to the Consolidated Financial Statements and primarily are comprised of interest expense on holding company debt, and unallocated corporate costs and activities.