13. An amount representing yield is payable in full to the account of the past component of a pension plan on the day following the date of any actuarial valuation of a pension plan after 30 December 2012. That amount is determined according to the following formula:
A × B, where
“A” represents the total, as at the date of the valuation, of the letters of credit refunded after 31 December 2011 to relieve the employer from paying an employer contribution to the past component;
“B” represents a weighted average determined by applying both the rate used for the purpose of applying the second paragraph of section 7 to the portion of such an employer contribution allocated to an amortization payment relating to the indexation deficiency, and the interest rates referred to in the second paragraph of section 6 to the other portion of such a contribution.