Since January 2008, the Euro Area has enlarged for the third time to Cyprus and Malta. As Slovakia is now planned to join in 2009, these waves of new entries revive the debate around greater asymmetries which may threaten the stability of the whole monetary union. This paper extends Bayoumi and Eichengreen's (1992) centre-periphery approach. We show how a suitable decomposition of the correlations between supply and demand disturbances enables to get two new indices to give a more intuitive assessment of the distance to the Euro area and the origin of shock asymmetries. Using monthly data over 1995-2008 on 21 countries, asymmetries are measured by correlations among the structural shocks from a VAR process. We then translate these correlati...