As the Regulation on Administrative Organisation and Staff Number Guideline of Local Education Authorities was revised in February 2012, the Total Payroll Costs System has been introduced in 17 area-wide provincial local education authorities. In order for the so called Total Payroll Costs System to be successfully introduced, some follow-up policy measures should be taken at practical level. One of them, first of all, is to map-out a specific and detailed regulations of enforcement regarding the calculation formula, by which the number of local government employees in provincial education authorities can be estimated. Under this background, this paper utilizes regression analysis method to set up a formula by which the optimal number of local government employees can be predicted. For this analysis, we also classify 17 local governments into four categories, reflecting regional and demographic characteristics. This paper, based on the analysis results, produces the fixed limit of staff number of each provincial education authority. In addition, it puts forward some policy suggestions for central government to be able to establish the system in a sustainable way at local level.