(1)Tax is charged under this Chapter on the full amount of the profits of the tax year.
(2)For this purpose the profits of a tax year are the profits of the basis period for the tax year.
(3)For the rules identifying the basis period for a tax year, see Chapter 15.
(4)This section is subject to Part 8 (foreign income: special rules).
(5)And, for the purposes of section 830 (meaning of “relevant foreign income”), the profits of a trade, profession or vocation arise from a source outside the United Kingdom only if the trade, profession or vocation is carried on wholly outside the United Kingdom.