Wisconsin Public Service Commission Docket No. 05-UR-107. Testimony for RENEW Wisconsin and Environmental Law & Policy Center before the Public Service Commission of Wisconsin re: Joint Application of Wisconsin Electric Power Company and Wisconsin Gas LLC to Conduct a Biennial Review of Costs and Rates for Test Year 2015. This surrebutal points out the flawed assumption in the witness' testimony and rebuttal. The flaw is that the broad and uncharacterized interests of "economic efficiency" will be advanced by aligning rate design with average class costs revealed in the Company's cost of service study. The assumption is unsupported in economic literature because they conflate the notions of average and marginal cost and pricing.