Recent killings in Paris as well as the arrival of hundreds of thousands of mostly Muslim refugees in Europe have drawn renewed attention to the continent’s Muslim population. In many European countries, including France, Belgium, Germany, the United Kingdom and the Netherlands, concerns about growing Muslim communities have led to calls for restrictions on immigration. But just how large is Europe’s Muslim population, and how fast is it growing?

Using the Pew Research Center’s most recent population estimates, here are five facts about the size and makeup of the Muslim population in Europe:

1. Germany and France have the largest Muslim populations among European Union member countries.
2. The Muslim share of Europe’s total population has been increasing steadily.
3. Muslims are younger than other Europeans.
4. Views of Muslims vary widely across European countries.
5. As of 2010, the European Union was home to about 13 million Muslim immigrants.

More information at: Pew Research Center