European Currency Unit European Currency Unit The European Currency Unit (₠ or ECU, ) was a basket of the currencies of the European Community member states, used as the unit of account of the European Community before being replaced by the euro on 1 January 1999, at parity. The ECU itself replaced the European Unit of Account, also at parity, on 13 March 1979. The European Exchange Rate Mechanism attempted to minimize fluctuations between member state currencies and the ECU. The ECU was also used in some international financial transactions, where its advantage was that securities denominated in ECUs provided investors with the
International status and usage of the euro is attractive for international transactions when it demonstrates stability, a well-developed financial market to trade the currency, and acceptability to others. While the euro has made substantial progress, a few challenges undermine the ascension of the euro as a major reserve currency. Persistent excessive budget deficits of some member nations, economically weak new members, conservatism of financial markets, and inertia or path dependence are important factors keeping the euro as a junior international currency to the US dollar. However, at the same time, the USD has increasingly suffered from a double deficit and has its own concerns. As the euro