(a) To provide for the support of increased net enrollments in the counties in a school year over the net enrollments used in the computation of total state aid for that year, there shall be appropriated for that purpose from the General Revenue Fund an amount to be determined as follows:
(1) The state board shall promulgate a rule pursuant to 29A-3B-1 et seq. of this code that establishes an objective method for projecting the increase in net enrollment for each school district. The state superintendent shall use the method prescribed by the rule to project the increase in net enrollment for each school district.