The approved final budget shall govern the expenditures of the county during the fiscal year. No expenses may be incurred in excess of those shown in the approved final budget, but the budget may be from time to time revised by the preparation and submission of a proposed amended budget by the county commissioners to the finance committee for approval. Only after the finance committee has approved an amended approved final budget, shall the amendment become effective. A report of approval of an amended budget shall be transmitted to the State Auditor within 15 days of an approval of an amended budget by the finance committee.   [PL 1989, c. 475, §§1, 2 (NEW).]