(a) Statutory good time means a credit to a sentence as authorized by 18 U.S.C. 4161. The total amount of statutory good time which an inmate is entitled to have deducted on any given sentence, or aggregate of sentences, is calculated and credited in advance, when the sentence is computed.

(b) Extra good time means a credit to a sentence as authorized by 18 U.S.C. 4162 for performing exceptionally meritorious service or for performing duties of outstanding importance in an institution or for employment in a Federal Prison Industry or Camp. “Extra Good Time” thus includes Meritorious Good Time, Work/Study Release Good Time, Community Corrections Center Good Time, Industrial Good Time, Camp or Farm Good Time, and Lump Sum Awards. Extra good time and seniority are inseparable with the exception of lump sum awards for which no seniority is earned.

(c) Seniority refers to the time accrued in an extra good time earning status. Twelve months of “seniority” automatically cause the earning rate to increase from three days per month to five days per month and seniority is then vested.

(d) Earning status refers to the status of an inmate who is in an assignment or employment which accrues extra good time.