S.D. Codified Laws § 58-15-36
In the case of a policy providing an amount of insurance varying with duration of the policy, the equivalent uniform amount thereof for the purpose of §§ 58-15-35 to 58-15-38, inclusive, shall be deemed to be the uniform amount of insurance provided by an otherwise similar policy, containing the same endowment benefit or benefits, if any, issued at the same age and for the same term, the amount of which does not vary with duration and the benefits under which have the same present value at the date of issue as the benefits under the policy, provided, however, that in the case of a policy providing a varying amount of insurance issued on the life of a child under age ten, the equivalent uniform amount may be computed as though the amount of insurance provided by the policy prior to the attainment of age ten were the amount provided by such policy at age ten.
SDCL 58-15-36