On and after June 16, 1944, the effective date of the amendment codified in this section, any person now receiving a pension under the terms of this chapter shall receive an amount based upon the average monthly rate of salary which such member received during the three years immediately preceding the date of retirement, and that said amount shall be a fixed amount that shall not increase or decrease, regardless of any change in salary subsequent to the date of the granting of the original pension for the rank or ranks that the member held prior to the granting of the pension. (Ord. 2627-NS (part), 1944: Ord. 2188-NS § 24.1, 1938)