A proposal for deposit must be sealed and delivered to the clerk and must have attached to it a statement showing the financial condition of the financial institution at that time and as disclosed in the several statements of financial condition made during the last preceding twelve months. The clerk shall lay the proposals before the board at the January meeting. Such proposals must be opened by the clerk in the presence of the board and the board, thereupon, shall proceed to designate a depository of public funds under its control.