Each local government and public authority shall appoint a budget officer to serve at the will of the governing board. In counties or cities having the manager form of government, the county or city manager shall be the budget officer. Counties not having the manager form of government may impose the duties of budget officer upon the county finance officer or any other county officer or employee except the sheriff, or in counties having a population of more than 7,500, the register of deeds. Cities not having the manager form of government may impose the duties of budget officer on any city officer or employee, including the mayor if he agrees to undertake them. A public authority or special district may impose the duties of budget officer on the chairman or any member of its governing board or any other officer or employee. (1971, c. 780, s. 1; 1973, c. 474, s. 6.)