32.1. At the end of each fiscal year the Retirement Board shall allow and credit regular interest, not to exceed 3.75 percent per annum beginning January 1, 2016, to each member’s account in the employees’ savings fund; said interest for a member shall be computed on the mean balance in his account during the year. At the end of each fiscal year the Board shall allow and credit regular interest on the mean balances in the pension accumulation fund and the pension reserve fund. The interest so allowed and credited shall be transferred from the income fund.