1. In these Rules the “net weekly income” of an offender means that offender’s weekly income (including income from overtime, commissions and bonuses) less—
(a)any tax payable on that income;
(b)any contributions payable by him under the Social Security Acts 1975—1988; and
(c)the amount of any contribution paid by him, whether under a legal obligation or not, to an occupational pension scheme within the meaning of the Social Security Pensions Act 1975 or to a personal pension scheme within the meaning of the Social Security Act 1986.