The board shall keep a record of its proceedings, which shall be open to public inspection. The board shall prepare annually and make available a report showing the financial condition of the plan which shall contain, but not be limited to, a financial balance sheet, a statement of income and disbursements, a detailed statement of investments acquired and disposed of during the year, together with a detailed statement of the annual rates on investment return from all assets and from each type of investment, a listing of all advisors and consultants retained by the board and such other data as the board shall deem necessary or desirable for a proper understanding of the condition of the plan.