Tex. Utilities Code § 53.051: ESTABLISHING OVERALL REVENUES.

In establishing a public utility's rates, the commission shall establish the utility's overall revenues at an amount that will permit the utility a reasonable opportunity to earn a reasonable return on the utility's invested capital used and useful in providing service to the public in excess of the utility's reasonable and necessary operating expenses.

Acts 1997, 75th Leg., ch. 166, Sec. 1, eff. Sept. 1, 1997.