Section 52.059 - Rates to Cover Appropriate Costs(a) The commission by rule shall adopt standards necessary to ensure that a rate established under this subchapter covers appropriate costs as determined by the commission.(b) Until standards are set under Subsection (a), the commission shall use a costing methodology that is in the public interest to determine whether a rate established under this subchapter covers appropriate costs. Acts 1997, 75th Leg., ch. 166, Sec. 1, eff. Sept. 1, 1997.