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
Irish pound changeover not related with the issue of coins. Decimalisation was overseen by the "Irish Decimal Currency Board", created on 12 June 1968. It provided changeover information to the public including a pamphlet called "Everyone's Guide to Decimal Currency". The changeover occurred on Decimal Day, 15 February 1971. In the 1970s, the European Monetary System was introduced. Ireland decided to join it in 1978, while the United Kingdom stayed out. The European Exchange Rate Mechanism finally broke the one-for-one link that existed between the Irish pound and the pound sterling; by 30 March 1979 an exchange rate was introduced. This period