The financial books and accounts of the city shall be audited as of the thirtieth day of June in each year by a competent person or persons appointed by the board of aldermen. The audit shall be presented to the board of aldermen and to the mayor within one hundred twenty (120) days of the first day of July. The board of aldermen or the mayor may order an audit of the financial books and accounts of the city by a competent person appointed by it or him at any time it or he may deem it proper so to do. (Acts 1951, Ch. 539, § 105; Reso. 9-5-63; Res. No. 3-76, § 1, 5-6-76)