Upon payment of a five percent (5%) contribution and interest of not to exceed five percent (5%) to the Oklahoma Public Employees Retirement System, a member of the Oklahoma Public Employees Retirement System shall receive service credit for any years of service the member had with the Oklahoma Employment Security Commission if the member is not receiving or eligible to receive service credit for the time in any other public retirement system; provided, however, effective January 1, 1990, the rate of contribution provided herein shall be ten percent (10%) and the rate of interest shall not exceed ten percent (10%), and effective January 1, 1991, to receive the service credit, the member shall pay the amount determined by the Board pursuant to Section 39 of this act.¹