§ 22-1002.  Actuarial Assumptions.
   (1)   Actuarial consultant. The Board shall designate the actuarial consultant who shall act as technical advisor to the Board on matters regarding the operation of the Retirement System and shall perform such other duties as are required in connection therewith.
   (2)   Interest rates; mortality tables; service tables; salary scales. The interest rates to be used in calculating the earnings of the reserves of the Retirement System, and the mortality tables, service tables and salary scales to be used in connection with the Retirement System (or any plan therein as applicable), shall be those adopted from time to time by the Board on the advice of the actuarial consultant.
   (3)   Actuarial investigations; valuation of assets and liabilities. At such times as the Board may deem it necessary, and at least once in each five-year period, the actuarial consultant shall make an actuarial investigation into the actual interest earned, mortality, service and compensation experience of the Retirement System (or any plan therein if appropriate), and shall make valuations of the assets and liabilities of the Retirement System.
   (4)   Modification of assumptions. The Board shall, from time to time, make and adopt such changes and modifications in the interest rates and mortality, service and other tables as shall be necessary for the Retirement System (or any plan therein, if appropriate).
   (5)   Valuations of actuarial effect due to legislation. Whenever the Board shall propose to Council, or Council shall have under consideration, any change in the provisions of this Title, or any other legislation affecting retirement benefits payable to City employees, the Board shall cause the actuarial consultant to make valuations of the actuarial effect of the change or such other legislation upon the assets and liabilities of the Retirement System (or any plan therein, if appropriate), and the Board shall promptly report the same, together with the Board's recommendations for approval or disapproval of the proposed change or legislation, to the Council.