Commentary on Sections Structure of Chapters Overview Section 536: Top slicing relieved liability: one chargeable event
2108.This section is based on sections 550 and 553 of ICTA.
2109.The method employed in subsection (1) takes three steps. The first step determines a fraction of the gain (called the “annual equivalent”). The second calculates the net tax charge that would apply to that fraction. The third step works out the tax on the whole gain (called the “relieved liability”) by multiplying the tax calculated under step 2 by the factor (“N” – see step 1) which was used to find the fraction.
2110.“N” represents the number of complete years the policy or contract has run before the chargeable event.
2111.Subsections (2) to (8)  contain rules which modify how “N” is worked out. For example, where the gain is from a “calculation event”, that is, a part surrender or assignment that gives rise to a gain, subsection (2) substitutes the number of years since the latest “calculation event” which arose on that policy or contract. (But, where the policy is a “new policy” (see subsection (5)) in relation to a replaced policy, any calculation event which arose on the replaced policy is disregarded for the purposes of subsection (2), even though the life of the “new policy” is, under subsection (4), dated from the commencement of the earlier replaced policy.)