15(1)Subject to sub-paragraph (2) below, tax charged in an assessment for a chargeable period shall carry interest at the rate of 9 per cent, per annum from four months after the end of the period until payment.
(2)Nothing in sub-paragraph (1) above shall authorise or require interest to be charged from any time before 30th April 1976.
(3)Where, under paragraph 14(3) above, tax may be withheld until the determination or abandonment of an appeal, the interest on that tax may also be withheld until the determination or abandonment of the appeal.
16Where any amount of tax charged by an assessment to tax becomes repayable under any provision of this Part of this Act that amount shall carry interest at the rate of 9 per cent, per annum from four months after the end of the chargeable period for which the assessment was made until repayment.