Calculation of bonus or commission
23. Where a claimant’s earnings include a bonus or commission to which regulation 16(6) (normal weekly earnings of employed earners) applies that part of his earnings shall be calculated by aggregating any payments of bonus or commission and dividing that sum by 52, less—
(a)an amount in respect of income tax equivalent to an amount calculated by applying to that part of the earnings the basic rate of tax in the year of assessment in which the claim is made;
(b)an amount in respect of primary Class 1 contributions under the principal Act equivalent to an amount calculated by applying to that part of the earnings the appropriate primary percentage applicable at the date of claim; and
(c)one half of any sum payable by the claimant in respect of that part of the earnings by way of a contribution towards an occupational or personal pension scheme.