S.D. Codified Laws § 10-4-12
If property owned by any health care organization or charitable, benevolent, or religious society described in § 10-4-9.4 and §§ 10-4-9 to 10-4-9.3, inclusive, other than agricultural land, is used partly by such health care organization or charitable, benevolent, or religious society for health care, charitable, benevolent, or religious purposes, and the remaining part is occupied, rented, or used for other than health care, charitable, benevolent, or religious purposes, the portion of property that is so occupied, rented, or used for other purposes, shall be taxed as other property of the same class is taxed. For the purpose of determining the value of the taxable portion of the property, the appraised value of the entire property shall be multiplied by the percentage of the entire property used for other than health care, charitable, benevolent, or religious purposes. The resulting value shall be multiplied by the percentage of time the property is used for other than health care, charitable, benevolent, or religious purposes. The resulting value shall be the assessed value for taxation purposes.
SDCL 10-4-12