116.1.1. For the calculation of a benefit, a contributor’s first additional pensionable earnings for each month are his first additional unadjusted pensionable earnings for that month multiplied by the ratio between the average Maximum Pensionable Earnings, referred to in the second paragraph of section 116.1, relating to the year for which the contributor’s average first additional monthly pensionable earnings are established and the Maximum Pensionable Earnings for the year that includes that month.
For any month of a year prior to the year 2023, the result obtained under the first paragraph is multiplied by one of the following factors, according to the year of the month concerned:
(a) 0.15 for the year 2019;
(b) 0.30 for the year 2020;
(c) 0.50 for the year 2021; or
(d) 0.75 for the year 2022.