(b) the aggregate of the three following amounts:(1) the total of his salary and wages determined under section 98.2.1 on the basis of the second additional contributions made and the amount obtained by dividing his second additional contribution in respect of his self-employed earnings and earnings as a family-type resource or an intermediate resource by the second additional contribution rate for the year,
(2) the total, determined in prescribed manner, of his salary and wages determined under section 98.2.2 on the basis of the second additional contributions made under a similar plan and the amount obtained by dividing his second additional contribution under such a plan in respect of his self-employed earnings by the second additional contribution rate for the year for a self-employed worker determined under such a plan, and
(3) the amount obtained by dividing double the second additional contributions that are unused for the purpose of computing the salaries and wages referred to in subparagraphs 1 and 2 by the second additional contribution rate for the year determined under section 44.3 or the second additional contribution rate for the year for a self-employed worker determined under a similar plan, according to the plan under which the worker is required to make a contribution; and