There were an estimated 216 million immigrants — people who permanently live outside of their home countries — worldwide in 2010, according to the National Organization for Migration. This number is about 3% of the global population. People immigrate for a variety of reasons, including to search for better economies, to receive higher education or to escape hostile conditions. Europe had the most immigrants, with about 70 million, followed by North America with about 45 million. The most popular destinations for immigrants in 2010 were the United States, with more than 42 million, followed by Russia with more than 12 million and Germany with more than 10 million. Mexico had the most people who had migrated elsewhere, with almost 12 million.
More about immigration:
Based on a 2012 survey, an estimated 640 million adults would migrate to another country if they could.
If the total number of immigrants were combined into one area, it would be the fifth-most-populous country in the world.
In 2010, there were an estimated 15.4 million refugees, or people who fled their home countries because of war or persecution.