Indiana Code Title 8. Utilities and Transportation § 8-1-2-10

Sec. 10. (a) Every public utility shall keep and render to the commission, in the manner and form prescribed by the commission, uniform accounts of all business transacted.  In formulating a system of accounting for any class of public utilities, the commission shall consider any system of accounting established by any federal law, commission, or department and any system authorized by a national association of such utilities.

(b) A public utility, municipally owned utility, or not-for-profit utility, including any utility owned, operated, or held in trust by a consolidated city, may defer for consideration by the commission and for future recovery costs incurred or to be incurred in a regulatory asset consistent with the accounting rules that concern the recognition of regulatory assets and that are in effect at the time the deferral decision is made by the utility, including any of the following costs, to the extent those specific costs are incremental and are not otherwise already included for recovery in the utility's rates:

(c) Commission preapproval for the creation of a regulatory asset is not required.

(d) Notwithstanding section 68 of this chapter, a utility described in subsection (b) may recover through the utility's rates over a reasonable period, as determined by the commission, costs that are: