No revenue from a new source not stated in the budget for the current budget year shall be included in the budget unless the city manager shall determine that the facts clearly warrant the expectation that such revenue will be actually realized in cash during the budget year in the amount stated and shall certify such determination in writing to the council. If the new revenue is to be received from the state, the anticipated amount shall not exceed the amount which the proper officer of the state shall declare in writing to be the amount which may reasonably be anticipated in the budget year.
Alabama Legal Code