As a requirement of EU membership, all Member States must adopt the common currency, the euro, once they have satisfied the criteria defined in the Maastricht Treaty on the Functioning of the European Union (this excludes Denmark and the UK, which have a specific opt-out from these Treaty provisions). There is no fixed timetable for the introduction of the euro in the Member States that joined in or after 2004, but the Treaty does require them to join the euro area at an undefined date in the future. Of the countries that joined the EU in or after 2004, Slovenia, Cyprus and Malta joined the euro area in 2007 and 2008; Slovakia followed in January 2009; Estonia joined in January 2011; Latvia joined in 2014; and Lithuania adopted the currency on 1 January 2015. With Lithuania having recently become the 19th euro area country, Sweden takes its place in this edition of the survey, joining Bulgaria, Croatia, the Czech Republic, Hungary, Poland, and Romania. Having joined the European Union in 1995, at least nine years prior to the other countries in this survey, attitudes and opinions are occasionally quite different for Sweden. Therefore, the average that comprises all seven countries should be compared to previous editions of this study with caution. This survey is the 17th in a series which began in 2004 and has helped the European Commission to track opinions, levels of knowledge and familiarity with the single currency among citizens regarding the future introduction of the common currency. The report looks at: levels of knowledge about and experience of the euro among citizens in the seven countries covered by the survey ; citizens' feelings about how well they have been informed about the euro and their preferred information channels for learning more about it ; citizens' perceptions of, and support for, the single currency and their expectations about the adoption of the euro both for themselves and for their country, and the potential positive or negative consequences they foresee. This survey was carried out by the TNS Political & Social network in the seven Member States that have not yet joined the euro area and have no specific opt-out, between 20 and 22 April 2015. Some 7,022 respondents from different social and demographic groups were interviewed via telephone in their mother tongue on behalf of the Directorate-General for Economic and Financial Affairs (DG ECFIN).
