Wis. Stat. § 76.10

(1) Every company defined in s. 76.02 shall, on or before October 1 in each year, be entitled, on its own motion, to present evidence before the department relating to the state assessment made in the preceding year pursuant to s. 70.575 . On request, in writing, for such hearing or presentation, the department shall fix a time therefor within 60 days after such application is filed, the same to be conducted in such manner as the department directs. Notice of such hearing shall be mailed to any company requesting a hearing and shall be published in the official state paper. Within 30 days after the conclusion of such hearing the department shall enter an order either affirming the state assessment or ordering correction thereof as provided in sub. (2) . A copy of such order shall be sent by certified mail to the company or companies requesting such hearing and to any interested party who has made an appearance in such proceeding. The department may, on its own motion, correct such state assessment. Any company having filed application for review of the state assessment pursuant to this section, or any other interested party participating in such hearing, if aggrieved by the order entered by the department, may bring an action in the circuit court for Dane County within 30 days after the entry of such order to have said order set aside and a redetermination made of the state assessment. In any such action or in any hearing before the department pursuant to this section, any interested party may appear and be heard. An interested party includes any division of government whose revenues would be affected by any adjustment of the state assessment.

(2) Whenever, in reviewing the valuation of the general property of the state, under the provisions of this section, the department shall determine that the valuation last made by it of the general property of the state under s. 70.575 was too high or too low, it shall adjust the next state assessment to correct such error; and any mistake discovered in any return, either by omission or otherwise, of any tax reported, or because of failure to report, shall be considered by the department in fixing the average tax rate for the year following, by adding to or deducting from the total tax returned the amount of such mistake or omission.