The European Currency Unit was abbreviated ECU and preceded the euro.
The ECU was a basket-based unit of account used by the European Economic Community and later the European Union. It was introduced on 13 March 1979 as part of the European Monetary System, with its value calculated from specified amounts of participating countries’ currencies. It helped coordinate exchange-rate policy without being a circulating currency used by shoppers.
The ECU was replaced by the euro at parity on 1 January 1999, when the euro became the official accounting currency for the new monetary union. Euro notes and coins followed in 2002. Although the ECU was not a physical predecessor in the same way that one national currency is replaced by another, its name, valuation framework, and financial role provided an important bridge to the euro.
ECU is easily confused with EMU, the Economic and Monetary Union, or ERM, the Exchange Rate Mechanism. SDR refers instead to the IMF’s Special Drawing Rights. The ECU’s ISO 4217 code was XEU, while ECU was its commonly used acronym.