Washington Revised Code Title 51. Industrial Insurance § 51.44.040. Second injury fund

(i) Except as provided in (a)(ii) of this subsection, the amount assessed each self-insurer must be in the proportion that the payments made from the fund on account of claims made against self-insurers bears to the total sum of payments from the fund.

(ii) Except as provided in section 2, chapter 475, Laws of 2005, beginning with assessments imposed on or after July 1, 2009, the department must experience rate the amount assessed each self-insurer as long as the aggregate amount assessed is in the proportion that the payments made from the fund on account of claims made against self-insurers bears to the total sum of payments from the fund. The experience rating factor must provide equal weight to the ratio between expenditures made by the second injury fund for claims of the self-insurer to the total expenditures made by the second injury fund for claims of all self-insurers for the prior three fiscal years and the ratio of workers' compensation claim payments under this title made by the self-insurer to the total worker's compensation claim payments made by all self-insurers under this title for the prior three fiscal years. The weighted average of these two ratios must be divided by the latter ratio to arrive at the experience factor.