Wyo. Stat. § 37-3-110
Within a time to be fixed by the commission, every public utility shall file with the commission, and keep open to public inspection as this commission may direct, schedules showing all rates for every service rendered or to be rendered by it. The commission may determine and prescribe the form of the schedules required by this act to be filed with the commission and kept open to public inspection and all changes therein, and change the form from time to time if it shall be found expedient; provided, however, that in respect to public utilities subject to act of congress to regulate commerce and any amendments thereof, the commission shall have such form or forms prescribed by it conform to any similar form prescribed by the surface transportation board.
W.S. 37-3-110