(1) The members' retirement fund is created. The fund shall accumulate reserves for the payment of retirement allowances to retired members and deferred vested members as provided in this act. Upon the basis of mortality and other experience tables, and the prescribed rate of interest, as the board shall adopt, the actuary shall compute annually the amount of retirement reserves for retirement allowances being paid to retirants and covering service rendered and to be rendered by members. It is the intention of this act that the retirement reserves shall be financed by other revenues to the fund and that annual appropriations shall be determined pursuant to subsections (2), (3), and (4).

    (2) The state's appropriation for current service shall be an amount that, if paid annually during the future service of members, will be sufficient to provide the reserves at the time of the members' retirement, after allowing for the net contributions to the members' savings fund to be made by the members, for the future service portions of the retirement allowances to which the members might become entitled.

    (3) The state's appropriation for members' accrued service shall be an amount that if paid annually over a period of years determined by the board, but not to exceed 50 years, will amortize at the prescribed rate of interest the unfunded reserves for the accrued service portions of the retirement allowances to which the members may become entitled.

    (4) The state's appropriation for retirement allowances being paid from the members' retirement fund shall be an amount that if paid annually over a period of years determined by the board, but not to exceed 50 years, will amortize at the prescribed rate of interest the unfunded reserves for the retirement allowances.

    (5) Notwithstanding any other provision of this act, if the retirement board establishes an arrangement and fund as described in section 6 of the public employee retirement benefit preservation act, the benefits that are required to be paid from that fund shall be paid from a portion of the employer contributions described in this section or other eligible funds. The retirement board shall determine the amount of the employer contributions or other eligible funds that shall be allocated to that fund and deposit that amount in that fund before it deposits any remaining employer contributions or other eligible funds in the pension fund.