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
Decimal Day officially authorized the United States as the first English-speaking nation to have decimalised currency, although Tsar Peter the Great used the concept for the Russian ruble close to a century earlier, in 1704, while China has used such a decimal system for at least 2000 years. The United Kingdom's Parliament rejected Sir John Wrottesley's proposals to decimalise sterling in 1824, which was prompted by the introduction in 1795 of the decimal French franc. After this defeat, little practical progress towards decimalisation was made for over a century, with the exception of the two-shilling silver florin (worth of a pound) first