Decimal Day use pennies or threepenny pieces, to pay them in multiples of 6d (p, the lowest common multiple of the two systems). Bus companies (at that time many state-owned by the National Bus Company) were another exception, going decimal on Sunday 21 February. Decimal Day itself went smoothly. Criticisms included the small size of the new halfpenny coin and the fact that some traders had taken advantage of the transition to raise prices. Some used new pennies as sixpences in vending machines. After 15 February, shops continued to accept payment in old coins, but always issued change in new coins. The
Coins of the pound sterling 10p and 50p coins. The pound coin (£1) was introduced in 1983 to replace the Bank of England £1 banknote which was discontinued in 1984 (although the Scottish banks continued producing them for some time afterwards; the last of them, the Royal Bank of Scotland £1 note, is still in production ). The designs on the one pound coin change annually in a largely five-year cycle. The decimal half penny coin was demonetised in 1984 as its value was by then too small to be useful. The pre-decimal sixpence, shilling and two shilling coins, which had continued to circulate alongside