Sec. 1320. (a) An impact fee ordinance must include:
(1) a schedule prescribing for each impact zone the amount of the impact fee that is to be imposed for each infrastructure type covered by the ordinance; or
(2) a formula for each impact zone by which the amount of the impact fee that is to be imposed for each infrastructure type covered by the ordinance may be derived.
(b) A schedule or formula included in an impact fee ordinance must provide an objective and uniform standard for calculating impact fees that allows fee payers to accurately predict the impact fees that will be imposed on new development.