(a) Except for purposes which are to be financed by the issuance of bonds or by special assessments, no money shall be drawn from the treasury of the city, except in accordance with the budget in effect and the appropriation for such purpose, nor shall any obligation for the expenditure of money be incurred without appropriation covering all payments which will be due under such obligation during the fiscal year.
(b) Expenditures shall not be charged directly to any contingent or general account; instead, the necessary amount of the appropriation from such account shall be transferred to the proper budget item or account and the expenditure then charged thereto. The Council, upon the written recommendation of the Mayor, and by the affirmative vote of not less than five (5) of its members, may appropriate unappropriated funds or transfer any unencumbered appropriation balance, or any portion thereof, from any budget item or account, department, or agency to another and make an appropriation thereof for the purpose for which such transfer is made. The Mayor shall be responsible for the administration of the foregoing requirements in subsection (a) and (b) of this section.
(c) During each month, the Mayor shall submit to the Council data showing the relation between the estimated and actual revenues and expenditures to the end of the preceding month; and, if it shall appear that the revenues are less than anticipated, the Council may, by resolution, reduce appropriations, except amounts required for debt and interest charges, to such a degree as may be necessary to keep expenditures within the revenues.
(d) Within thirty (30) days following the end of each fiscal year, the Mayor shall file with the Council a schedule of all encumbrances upon the budget appropriations existing at the end of the fiscal year, with his recommendations thereon, and the Council shall provide for the payment of such thereof as constitute valid claims against the city from corresponding budget items appropriated in the then- current fiscal year.