S.C. Code Ann. § 9-8-240
Effective as of January 1, 1996, the annual compensation of a member taken into account for determining all benefits provided under this retirement system is subject to the limitations set forth in Section 401(a)(17) of the Internal Revenue Code of 1986 and any regulations promulgated thereunder. However, the limitation on compensation does not apply to the compensation of an individual who became a member of this retirement system before January 1, 1996.