(a) Compensation for total or partial disability may not exceed 75 percent of the basic monthly pay of the highest step of grade 15 of the General Schedule. (Basic monthly pay does not include locality adjustments.) However, this limit does not apply to disability sustained in the performance of duty which was due to an assault which occurred during an attempted assassination of a Federal official described under 18 U.S.C. 351(a) or 1751(a).

(b) Compensation for total disability may not be less than 75 percent of the basic monthly pay of the first step of grade 2 of the General Schedule or actual pay, whichever is less. (Basic monthly pay does not include locality adjustments.)