Each utility shall so keep the records supporting the entries to each electric sales account that it can furnish (a) the name of each customer, (b) the quantity of electric energy furnished to each customer, (c) the amount charged for electric energy furnished each customer, and (d) the service classifications under which the charge is made. Each utility shall also be prepared to report upon request, within a reasonable time, for each month or other billing period and for each year, the quantity of energy sold and the charges therefor, by service classifications.
N.Y. Comp. Codes R. & Regs. Tit. 16 § 183.6