Unit of account L.S.D units in ratio 240:12:1. The Florentine gold florin, the French franc and the electoral rheingulden all became pounds (240 denari) of account. Units of account would often survive over 100 years despite the original coins changing composition and availability (e.g. the Castilian maravedi). A modern unit of account is the European Currency Unit, used in the European Union from 1979 to 1998; its replacement in 1999, the Euro, was also just a unit of account until the introduction of notes and coins in 2002. Unit of account is the main way of calculating a carrier or ship owner's liability
20 euro note over 300 million people in Europe. For the first three years of its existence it was an invisible currency, only used in accountancy. Euro cash was not introduced until 1 January 2002, when it replaced the national banknotes and coins of the countries in eurozone 12, such as the Belgian franc and the Greek drachma. Slovenia joined the Eurozone in 2007, Cyprus and Malta in 2008, Slovakia in 2009, Estonia in 2011, Latvia in 2014, and Lithuania in 2015. The changeover period during which the former currencies' notes and coins were exchanged for those of the euro lasted about two