22. For the purposes of sections 19 and 20, the amount of pension that would be obtained on the basis of the sums awarded to the spouse at the date of assessment is established at that date in accordance with the actuarial method and assumptions in section 8. That amount is presumed applicable at the date of assessment.
The amount of pension obtained pursuant to the first paragraph is increased by 0.50% per month, computed for each month between the date of assessment and the date on which that amount of pension begins to apply, if the pension was being paid on the date of assessment or would have been if the former judge had made an application to that effect, or for each month between the date of retirement and the date on which that amount of pension begins to apply, if the pensioner retired between the date of assessment and the date of payment.