Mo. Rev. Stat. § 87.165: Actuarial investigation — establishment of contribution rates and tables.

1. The actuary shall be the technical adviser of the board of trustees on matters regarding the operation of the funds created by sections 87.120 to 87.370 and shall perform such other duties as are required in connection therewith. He shall be qualified by membership as a fellow in the Society of Actuaries.

2. The board of trustees shall have made every five years an actuarial investigation into the mortality, service and compensation experiences of the members and beneficiaries of the retirement system and, taking into account the results of such investigation and valuation, the board of trustees shall establish for the retirement system such mortality, service and other tables as are deemed necessary.

3. On the basis of the tables as the board of trustees adopt, the actuary shall make an annual valuation of the assets and liabilities of the funds of the system.

4. On the basis of the valuation the board of trustees shall certify the rates of contribution payable by the city.