The board of trustees shall prescribe in its bylaws the method of valuation of assets, which method shall be in accordance with acceptable accounting practices in use by corporate trustees. (Ga. L. 1965, p. 421, § 18.) 47-5-26. Duty of board of trustees to file an annual financial report with each member employer; filing of objections to transactions shown in such report. The board of trustees shall file with each member employer an annual written report showing pertinent transactions affecting its respective retirement fund account, workers’ compensation fund account, or employee benefit fund account since the last previous such report. Within 90 days of the receipt of such report, a member employer may file written objections with the board of trustees with respect to any transactions regarding its account as shown in such report. (Ga. L. 1965, p. 421, § 22; Ga. L. 1984, p. 1041, § 7.) 47-5-27. Payment of administrative expenses of the board of trustees; allocation of expenses among member municipalities. The administrative expenses of the board of trustees, including all operational expenses, fees, compensation, and other costs, shall be paid from funds held by it and may be chargeable by it to either principal or income or both, as determined by it, as of any valuation date. Further, the board of trustees shall have the authority to allocate expenses among member municipalities on the basis of costs. Administrative expenses for the first year of operation may be assessed against first year contributions in proportion to the number of participating employees. (Ga. L. 1965, p. 421, § 23; Ga. L. 1966, p. 539, § 7.) 47-5-28. Accounts for participating employees, member employers, and as otherwise required; authorization of funds; commingling restriction. (a) The board of trustees shall administer the retirement fund and shall maintain records as follows: (1) The board of trustees shall maintain individual accounts for each participating employee, to which shall be credited the dollar value of participation allocated to such employee under the respective member 388 47-5-29 employer’s retirement plan, and such other accounts, if any, as may be reasonably required, in the discretion of the board of trustees, for the convenient administration of the plan; (2) There shall be credited to the contribution account of each member employer all contributions received by the board of trustees from it or its participating employees and there shall be charged against such account all payments made from it pursuant to the terms of the retirement plan, together with any other payment or expenses chargeable against that account; (3) The interest of each member employer in any retirement fund established under the system shall be represented by units which shall constitute equal interest in any such fund; and (4) The board of trustees may from time to time establish new or additional retirement funds and may separate and place new contributions in such funds instead of adding to existing funds, provided that member employers continue to be represented by units which constitute equal interests in such funds. (b) The board of trustees may establish a workers’ compensation fund, employee benefit fund, and other funds necessary or incident to the provision of workers’ compensation benefits and employee benefits under this chapter. (c) The retirement fund shall not be commingled with the workers’ compensation fund, employee benefit fund, or other funds. (Ga. L. 1965, p. 421, § 18; Ga. L. 1966, p. 539, § 6; Ga. L. 1984, p. 1041, § 8.)