306.5. The value as at 31 December 1997 of the reductions referred in sections 306.3 and 306.4 must be calculated using the same interest assumption as that used for the actuarial valuation of the pension plan effected as at 31 December 1997. However, the city and the employees’ associations representing the majority of the members of the plan may agree in writing that the value of the reductions be calculated according to the interest assumption utilized in any valuation effected as at a later date; in such a case the plan must be amended to provide for the method of calculation of that value. Moreover, no reduction may be made that would cause an amount payable to be determined pursuant to subparagraph 4 of the second paragraph of section 137 or to be higher than it would have been without the reduction.
The amounts payable according to subparagraph 1 of the first paragraph of section 306.2 may not be reduced except in a proportionate manner and through the utilization of the gain determined in the actuarial valuation under section 30 of the Act respecting the negotiation of agreements concerning the reduction of labour costs in the municipal sector (1998, chapter 2). In addition, the amount referred to in subparagraph 2 of the first paragraph of section 306.2 shall be adjusted as at 31 December 1997 in such a manner that, after the application of paragraph 2 of section 306.3 or of subparagraph 1 of the first paragraph of section 306.4, the present value as at that date of the reduction of the amortization amounts that had been identified in the report referred to in the second paragraph of section 306.2 and that, according to that report, were required to be paid from that date until 31 December 2007 becomes equal to 50% of the value of the reduction of all the amortization amounts relating to the unfunded actuarial liability referred to in the second paragraph of section 135.3.