All income remaining after allocation pursuant to Sections 12-6-2220 and 12-6-2230 is apportioned in accordance with Section 12-6-2252, or one of the special apportionment formulas provided in Sections 12-6-2290 through 12-6-2310.
Apportionment of all income remaining after allocation
S.C. Code Ann. § 12-6-2240, under Title 12, Chapter 6.
S.C. Code Ann. § 12-6-2240