There shall be paid annually, in equal monthly installments, out of the general funds of the several incorporated municipalities of Mobile County to the board of health of such county such sums of money as shall be reasonably necessary for the county health department, for the acquisition of land, the erection, construction, extension, renewal, and repair of any buildings and improvements thereon, and for the maintenance and operation of such department, under the direction of the county health officer, which sum for any fiscal year after September 30, 1987, shall not be less than a sum equal to one dollar seventy-five cents ($1.75) per capita of population according to the last or any succeeding federal census, and which sum for any fiscal year after September 30, 1989, shall not be less than a sum equal to two dollars ($2) per capita of population according to the last or any succeeding federal census. The amount to be appropriated each year shall be determined by the governing body of the county under the foregoing rules and directions. After fiscal year ending September 30, 1989, the sum shall not be less than a sum equal to two dollars ($2) per capita of population according to the last or any succeeding federal census. Such sum may be anticipated, but for not longer than 12 months, by temporary loan certificates issued by the county board of health, and, when anticipated, the proceeds shall be used for the same purposes as the sum so appropriated.