Section 3(1): amended, on 24 February 2016, by section 301 of the Taxation (Annual Rates for 2015–16, Research and Development, and Remedial Matters) Act 2016 (2016 No 1).
Section 3(3): substituted, on 8 August 1991, by section 28 of the Finance Act 1991 (1991 No 93).