lump-sum credit
(8) “lump-sum credit” means the compulsory and special contributions to the credit of a participant or former participant in the Fund plus interest on such contributions at 4 percent a year compounded annually to December 31, 1976 , and after such date, for a participant who separates from the Service after completing at least 1 year of civilian service and before completing 5 years of such service, at the rate of 3 percent per year to the date of separation (except that interest shall not be paid for a fractional part of a month in the total service or on compulsory and special contributions from an annuitant for recall service or other service performed after the date of separation which forms the basis for annuity);