(1) The board has the authority to establish the rates to be charged by the state fund and the supplementary rate information to determine the applicable premium as provided in 39-71-2311 and 39-71-2316 and shall file the rates and supplementary rate information with the commissioner as provided in Title 33, chapter 16. The board shall engage the services of an independent actuary who is a member in good standing with the American academy of actuaries to develop and recommend actuarially sound rates. Rates must be set at amounts sufficient, when invested, to carry the estimated cost of all claims to maturity, to meet the reasonable expenses of conducting the business of the state fund, and to amass and maintain an excess of surplus over the amount produced by the national association of insurance commissioners' risk-based capital requirements for a casualty insurer.
(2) Because surplus is desirable in the insurance business, the board shall annually determine the level of surplus that must be maintained by the state fund pursuant to this section. The state fund shall use the amount of the surplus above the risk-based capital requirements to secure the state fund against various risks inherent in or affecting the business of insurance and not accounted for or only partially measured by the risk-based capital requirements.
(3) The board may establish multiple rating tiers for classifications that take into consideration losses, premium size, and other factors relevant in placing an employer within a rating tier. The board shall file any multiple rating tiers with the commissioner for review as provided in Title 33, chapter 16.