About 12% of the population declared that they have no religion. in 2001; this share had grown to 20% by 2015. Of the remaining people, around 340,000 were registered as members of various Muslim communities in 2001, mainly due to the influx from Turkey, Bosnia-Herzegovina and Kosovo. The number of Muslims has doubled in 15 years to 700,000 in 2016. About 680,000 are members of Orthodox Churches (mostly Romanians and Serbs), about 21,000 people are active Jehovah's Witnesses and about 8,100 are Jewish.