The expenditure limitation for all school districts in the state of Arizona is governed by Arizona Revised Statutes, Title 15.
All school districts determine the expenditure limitation by the use of state mandated formulas.
The largest portion of the expenditure limitation is based upon each school district's weighted average daily membership times a base level support per student. The base level support per student was set by legislative action and is increased each year by the Gross National Product Price Deflator or an amount determined by the legislature. The average daily membership is determined by counting the number of students enrolled each day for the first 100 days of the previous school year and then dividing by 100. Weights, set by the State, are applied to various categories of students. The weights are a result of numerous studies that indicate the variance in cost of educating different categories of students.