S.D. Codified Laws § 10-44-9.5
Upon receipt of the funds as provided in § 10-44-9.4 each county auditor shall determine the amount to be received by each certified fire department servicing the county, including those domiciled outside the county. All the funds received shall be divided one-half in the same ratio as the assessed valuation of all property within the service area of the department to the assessed valuation of all property within the service areas of all fire departments within the county, and one-half in the same ratio as the population of the area serviced by the department to the population within the service areas of all fire departments within the county. The county auditor shall base the allocation on figures contained in the most recent published annual statistical report of the Department of Revenue, and census or population estimates of the United States Department of Commerce Bureau of the Census.
SDCL 10-44-9.5