Versions of s. 147.1(1), definition “permitted corrective contribution”, para (a)

the total of all amounts each of which is an amount, for a retroactive year, determined by the formula A + B − C where A is the total of all amounts each of which is an amount by which a contribution required to be made at a particular time in the retroactive year under the provision in respect of the individual exceeds the amount contributed at the particular time in respect of the individual, B is the amount of interest, if any, calculated in respect of each amount determined for A at a rate that is required by the Pension Benefits Standards Act, 1985 or a similar law of a province, or if subparagraph (i) does not apply, does not exceed a reasonable rate, and C is the total amount previously contributed to the provision in respect of the individual under subsection (20) for the retroactive year, and