(b) Based upon the provisions of section thirteen of this article, the participating public employers' contributions to the retirement system, as determined by the Consolidated Public Retirement Board by legislative rule promulgated in accordance with the provisions of article three, chapter twenty-nine-a of this code, shall be a percent of the members' total annual compensation related to benefits under this retirement system. In determining the amount, the Board shall give consideration to setting the amount at a sum equal to an amount which, if paid annually by the participating public employers, will be sufficient to provide for the total normal cost of the benefits expected to become payable to all members and to amortize any unfunded liability found by application of the actuarial funding method chosen for that purpose by the Consolidated Public Retirement Board, over a period of years determined actuarially appropriate. When proposing a rule for promulgation which relates to the amount of employer contribution, the Board may promulgate emergency rules pursuant to the provisions of article three, chapter twenty-nine-a of this code, if the inability of the board to increase employer contributions will detrimentally affect the actuarial soundness of the retirement system. A signed statement from the state actuary shall accompany the statement of facts and circumstances constituting an emergency which shall be filed in the State Register. For purposes of this section, subdivision (2), subsection (b), section fifteen-a, article three, chapter twenty-nine-a of this code is not applicable to the Secretary of State's determination of whether an emergency rule should be approved.