1184. Where the tax otherwise payable by a taxpayer under section 1179 for a taxation year exceeds the aggregate of the amounts that he may effectively deduct for the year in respect of that tax under section 1183 and section 127 of the Income Tax Act (Revised Statutes of Canada, 1985, chapter 1, 5th Supplement),(a) the excess must be applied in reduction of that tax in the case where it does not result in a decrease in the amount that the taxpayer may effectively deduct for the year under the said section 127; and
(b) in any other case, the excess must be applied to reduce, in addition to the amount provided for in section 1183, the tax otherwise payable under Part I, for the year or for any subsequent taxation year.