Euro states; it was not a currency in its own right. They could not be set earlier, because the ECU depended on the closing exchange rate of the non-euro currencies (principally the pound sterling) that day. The procedure used to fix the conversion rate between the Greek drachma and the euro was different, since the euro by then was already two years old. While the conversion rates for the initial eleven currencies were determined only hours before the euro was introduced, the conversion rate for the Greek drachma was fixed several months beforehand. The currency was introduced in non-physical form (traveller's
History of the euro on 9 December 2011 by the European Council. The participants are the eurozone member states and all other EU members without the United Kingdom and the Czech Republic. The treaty entered into force on 1 January 2013 for the 16 states which completed ratification prior of this date and on 1 April 2014 entered into force for all 25 signatories. Despite speculation that the crisis in Greece could spread and that the euro might fail, some newer EU states from the 2004 enlargement joined the currency during the recession. Slovenia, Malta and Cyprus all acceded within the first two years