The economy of Europe comprises more than 740 million people in 50 different countries. Like other continents, the wealth of Europe's states varies, although the poorest are well above the poorest states of other continents in terms of GDP and living standards. The end of World War II brought European countries closer together, culminating in the formation of the European Union (EU) and in 1999, the introduction of a unified currency – the euro. The difference in wealth across Europe can be seen roughly in former Cold War divide, with some countries breaching the divide (Greece, Portugal, Slovenia and the Czech Republic). Whilst most European states have GDP per capita higher than the world's average and are very highly developed(Liechtenstein, Luxembourg, Monaco, Andorra, Norway, Sweden, the Netherlands, Switzerland), some European economies, despite their position over the world's average (except for Moldova) in the Human Development Index (Albania, Armenia, Azerbaijan, Bosnia and Herzegovina, Georgia, Macedonia, Kosovo, Serbia, Belarus, Ukraine) are poorer.