From this report onwards, nominal and real effective exchange rates will be calculated based on a reference group of 41 countries. By extending the group of reference countries from 24 countries to 41 countries, more than 80% of extra EU12-exports instead of 58% will be covered. The effective exchange rate calculations will consequently better reflect the trade pattern. In addition, the new Member States are included in the reference group. The report contains data for the European Union Member States as well as the United States and Japan. Aggregate measures for the European Union as a whole (EU) and the group of countries participating in the euro area (EUR-12) are presented as well.