If, in any adjustment year, the amount payable to the constituent municipalities by the intermunicipal account for guarantee payments and service payments exceeds the amount payable to said account pursuant to section 65 of this act, the total service payments payable to all constituent municipalities shall be reduced by the amount of the deficit and the service payment payable to each constituent municipality shall be reduced by the same ratio as the total service payment to all constituent municipalities was reduced.
N.J.S. § 13:17-73