56.5. A worker’s salary and wages on which a second additional contribution has been made for a year under a similar plan is equal to the lesser of(a) the amount by which the aggregate of all amounts each of which is the worker’s pensionable salary and wages for the year in respect of pensionable employment under the similar plan exceeds the proportional share of the worker’s maximum pensionable earnings for the year under the plan;
(b) the amount by which the proportional share of the worker’s additional maximum pensionable earnings for the year under the similar plan exceeds the proportional share of the worker’s maximum pensionable earnings for the year under the plan; and
(c) the amount obtained by dividing, by the second additional contribution rate for employees for the year under the similar plan, the aggregate ofi. the aggregate of the deductions at source from the worker’s salary and wages for the year on account of the second additional contribution under this Act or a similar plan and any amount that an employer has not deducted at source from the worker’s salary and wages for the year on account of the second additional contribution, as the employer should have done under this Act or a similar plan, provided that the worker has given notice of that fact to the Minister on or before 30 April of the following year, and
ii. the aggregate of the amounts established under subparagraph b of the second paragraph of section 56 and subparagraph b of the second paragraph of section 56.2.