(a) The board shall prepare and approve an annual budget.
(b) The budget shall contain a complete financial statement, including a statement of:
(1) the outstanding obligations of the district;
(2) the amount of cash on hand to the credit of each fund of the district;
(3) the amount of money received by the district from all sources during the previous year;
(4) the amount of money available to the district from all sources during the ensuing year;
(5) the amount of the balances expected at the end of the year in which the budget is being prepared;
(6) the estimated amount of revenues and balances available to cover the proposed budget; and
(7) the estimated tax rate that will be required.