98.2. The second additional unadjusted pensionable earnings of a contributor for a year are an amount equal to the least of the three following amounts:(a) the amount by which the total of the amounts referred to in subparagraph a of the first paragraph of section 98 exceeds his maximum pensionable earnings for the year;
(b) the aggregate of the two following amounts:(1) the total of his salary and wages on which a second additional contribution has been 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, and
(2) the total, determined in prescribed manner, of his salary and wages on which a second additional contribution has been made under a similar plan and the amount obtained by dividing his second additional contribution under such 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 plan; and
(c) the amount by which his additional maximum pensionable earnings for the year exceed his maximum pensionable earnings for the year.