(1)General betting duty is charged on a Chapter 1 pool bet made with a bookmaker.
(2)It is charged at the rate of 15% of the bookmaker’s profits on Chapter 1 pool bets for an accounting period.
(3)The bookmaker’s profits on Chapter 1 pool bets for an accounting period are the aggregate of—
(a)the amount of the bookmaker’s profits for the period in respect of pooled stake Chapter 1 pool bets (calculated in accordance with section 136), and
(b)the amount of the bookmaker’s profits for the period in respect of ordinary Chapter 1 pool bets (calculated in accordance with section 137), and
(c)the amount of the bookmaker’s profits for the period in respect of retained winnings on Chapter 1 pool bets (calculated in accordance with section 138).
(4)Where the calculation for an accounting period under subsection (3) produces a negative amount—
(a)the bookmaker’s profits on Chapter 1 pool bets for the accounting period are treated as nil, and
(b)the amount produced by the calculation may be carried forward in reduction of the bookmaker’s profits on Chapter 1 pool bets for one or more later accounting periods.