1121.2. The particular amount referred to in section 1121.1 for a taxation year of a mutual fund trust in respect of a particular unit thereof is equal to the aggregate of(a) such amount as the trust may determine in respect of the particular unit for the year not exceeding the amount by which the aggregate of all amounts determined by it under section 670, as that section read before being repealed, for its taxation years commencing before 1 January 1988 exceeds the aggregate of those determined by it under this paragraph for the year or a preceding taxation year in respect of all its units, except the amount determined by it in respect of the particular unit for the year under this paragraph;
(b) such amount as the trust may determine in respect of the particular unit for the year not exceeding the amount by which the aggregate of all amounts described in subparagraph i.1 of paragraph n of section 257 that became payable by the trust after 31 December 1987 and before the year exceeds the aggregate of those determined by it under this paragraph for the year or a preceding taxation year in respect of all its units, except the amount determined by it in respect of the particular unit for the year under this paragraph.