(1) Section 162 of the Corporation Tax Act, 1976, is hereby amended in subsection (4) -
(a) by the substitution of "15 per cent." for "20 per cent.", and
(b) by the insertion in the proviso to that subsection of the following paragraph after paragraph (ii):
"(iii) the surcharge shall apply to so much of the excess calculated under this subsection in respect of an accounting period of a company as is not greater than the excess of the aggregate of the distributable investment income and the distributable estate income of the accounting period over the distributions of the company for the accounting period as if the reference in this subsection, apart from this paragraph, to 15 per cent. were a reference to 20 per cent.".
(2) This section shall apply and have effect as respects accounting periods ending on or after the 1st day of April, 1996:
Provided that for the purpose of this section where an accounting period begins before the 1st day of April, 1996, and ends on or after that d