On January 1, 1999, the European Union introduced its new currency, the euro. The euro was created to promote growth, stability, and economic integration in Europe. Originally, the euro was an overarching currency used for exchange between countries within the union. Andorra, Monaco, San Marino, and Vatican City have formal agreements with the EU to use the euro as their official currency and issue their own coins. The euro is the official currency for 19 of the 27 EU member countries.