500 euro note 26 April 2019. “Authorities increasingly suspect that they (€500 notes) are being used for illegal purposes, an argument that we can no longer ignore,” according to a high-ranking bank official, Benoît Cœuré. The euro was founded on 1 January 1999, when it became the currency of 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 Luxembourgish franc. Slovenia joined the
World currency unit have adopted the name "World Currency Unit". The Wocu (contraction of World Currency Unit) is a standardized basket of currencies — the national currencies of the 20 largest national economies measured by GDP, established in 2008. The basket is reweighed semi-annually according to the relative growth of the economies, whereby constituent currencies are replaced by other currencies should the size of the GDP be overtaken by that of another national economy. Conceived as an apolitical and global alternative to the ECU, it is used as a reference currency for global investors and companies seeking to mitigate bilateral exchange rate volatility.