The free movement of people accord is in the line of fire as Europe battles with its migration crisis. But which European countries have more people leaving than arriving? We took a look at the data.
It's over 14 years since the free movement of people accord between Switzerland and the European Union came into force. Thanks to this deal, Swiss and EU citizens can study, work and retire in any EU country and in the European Free Trade Association (EFTA) zone of Norway, Switzerland, Liechtenstein and Iceland.
The free movement of people is one the EU's four basic rights guaranteed by the accord, along with that of goods, finance and services.
Now Switzerland and the UK are both grappling with referendum results requiring immigration curbs. As the last installment of this migration series showed, more people migrate from within Europe than from Africa, something spurred on by the free movement of people.
As the chart below shows, the migration surplus differs by region. Unsurprisingly, the richest countries attract the most migrants. Switzerland, Germany, Austria and the UK, as well as Scandinavia, have surplus migration.
There were over 37.7 million foreigners in EU and EFTA countries in 2015 - 8% of the total population. More than 45% of these foreigners were from an EU or EFTA state.
A large proportion of the immigrants come from Eastern and Southern Europe. Romanians and Poles account for around 30% of foreigners in the EU and EFTA, although the state of immigration differs wildly from country to country. The below graphic shows the nationalities of immigrants in different countries.
Different studies have shown that the free movement of people generally has a positive effect on host countries and the costs of immigrants are typically outweighed by the benefits.
Less clear are the costs to those countries people have emigrated from. According to a study by the International Monetary Fund, an exodus of young and educated workers could halt economic and demographic growth in Eastern Europe.
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Translated from French by Jessica Dacey