S.C. Code Ann. § 12-6-3330
(B) The credit is limited to seven-tenths of one percent multiplied by the lesser of:
(C)
(1) South Carolina qualified earned income is computed as follows:
(2) The term "South Carolina earned income" means income that is earned income within the meaning of Internal Revenue Code Section 911( d)(2) or 401(c)(2) and is taxable in this State, except that:
(a) it does not include an amount: