Wis. Stat. § 620.32: Investment valuation reserves.

(1) General. The commissioner may by rule, applicable to all or specified classes of insurers, provide for the establishment in reasonable amounts of investment valuation reserves that are necessary and appropriate to lessen the impact on surplus of the fluctuation of the values of specific classes of assets.

(2) Specific. The commissioner may by order require an individual insurer to establish investment valuation reserves in addition to those required for other insurers of the class to which the insurer belongs, to the extent that the financial condition of the insurer and the nature of its assets and liabilities or business require that such reserves be established for the adequate protection of its insureds.

(3) Uniformity. So far as reasonably possible, reserves required under sub. (1) shall correspond with those generally required in other states.