The number of unauthorized immigrants living in Europe increased between 2014 and 2016, then leveled off to an estimated 3.9 million to 4.8 million in 2017, according to new estimates from Pew Research Center.
Nearly 13 million Syrians are displaced after seven years of conflict in their country. No nation in recent decades has had such a large percentage of its population displaced.
In all, more than half a million asylum seekers from Syria during the 2015-16 migration surge had received permission to stay in Europe as of Dec. 31, 2016.