(1) Working papers shall show the total annual cost of power or gas purchased for the 12 months test period of actual experience, the claimed adjustments thereof, if any, and the total adjusted cost for the test period detailed by major category. If any of the prices are effective subject to refund, there shall be shown by major category and by commission docket number for the test period, the rate and the amount paid subject to refund.

(2) If the utility purchases and sells power under exchange or pooling argeements, the method of recording on books, total gross receipts and deliveries exchanged, total gross dollar amounts involved for such receipts and deliveries and details of such exchanges shall be submitted.