209.0.1. In computing the income of a taxpayer for a taxation year ending after 31 December 1990 from a business carried on by the taxpayer throughout the year as an insurance agent or broker, there may be deducted as an additional reserve in respect of unearned commissions an amount not exceeding(a) where the year ends in 1991, 90%,
(b) where the year ends in 1992, 80%,
(c) where the year ends in 1993, 70%,
(d) where the year ends in 1994, 60%,
(e) where the year ends in 1995, 50%,
(f) where the year ends in 1996, 40%,
(g) where the year ends in 1997, 30%,
(h) where the year ends in 1998, 20%,
(i) where the year ends in 1999, 10%, and
(j) where the year ends after 31 December 1999, 0%