Versions of s. 61.4(a)

the amount determined by the formula A - B where A is the amount, if any, by which the total of all amounts each of which is an amount that, because of the application of section 80 to a commercial obligation (within the meaning assigned by subsection 80(1)) issued by the taxpayer (or a partnership of which the taxpayer was a member) was included under subsection 80(13) in computing the income of the taxpayer for the year or a preceding taxation year or of the partnership for a fiscal period that ends in that year or preceding year (to the extent that, where the amount was included in computing income of a partnership, it relates to the taxpayer’s share of that income) exceeds the total of all amounts each of which is an amount deducted under paragraph 80(15)(a) in computing the taxpayer’s income for the year or a preceding taxation year, and all amounts deducted under section 61.3 in computing the taxpayer’s income for the year or a preceding taxation year, and B is the amount, if any, by which the amount determined for A in respect of the taxpayer for the year exceeds the total of the amount that would be determined for A in respect of the taxpayer for the year if that value did not take into account amounts included or deducted in computing the taxpayer’s income for any preceding taxation year, and the amount, if any, included under section 56.3 in computing the taxpayer’s income for the year,