The Euro is the common currency which was adopted at the end of the 90s by the majority of countries in the European Union and which substituted the various national currencies starting of the 1st of January 2002, three years after the official founding of the Euro and the block between the exchange rates of the various countries. 19 of the 28 European states have officially adopted the Euro, in addition the the states of the Vatican, San Marino, Andorra, Monaco, Kosovo and Montenegro.