(a) When a school system meets all the requirements stated in O.C.G.A. '20-2-292 and its annual average FTE continues to remain below the following sizes,the calculation of the system's sparsity grant for each subsequent year will be based on the increase or decrease in the system's FTE after the original feasibility study was completed.
1. Elementary School -- 450 FTE.
2. Middle School -- 624 FTE.
3. High School -- 485 FTE.