Non-decimal currency Non-decimal currency A non-decimal currency is a currency that has sub-units that are a non-decimal fraction of the main unit, i.e. the number of sub-units in a main unit is not a power of 10. Today only two countries in the world use non-decimal currencies. Both of these countries are in Africa. These are Mauritania (1 ouguiya = 5 khoums) and Madagascar (1 ariary = 5 iraimbilanja). However these are only theoretically non-decimal, as in both cases the value of the main unit is so low that the sub-unit is too small to be of any practical use and coins
Coins of the pound sterling exact decimal equivalent values continued in use after 1971 alongside the new coins, albeit with new names (the shilling became equivalent to the 5p coin, with the florin equating to 10p), and the others were withdrawn almost immediately. The use of florins and shillings as legal tender in this way ended in 1991 and 1993 when the 5p and 10p coins were replaced with smaller versions. Indeed, while pre-decimalisation shillings were used as 5p coins, for a while after decimalisation many people continued to call the new 5p coin a shilling, since it remained of a pound, but was now