In addition to other taxes, there is hereby imposed on the income of each employee representative a tax equal to the applicable percentage of the compensation received during any calendar year by such employee representative for services rendered by such employee representative. For purposes of the preceding sentence, the term “applicable percentage” means the percentage equal to the sum of the rates of tax in effect under subsections (a) and (b) of section
3101 and subsections (a) and (b) of section
3111 for the calendar year.