Islam is the predominant religion in Algeria, with its adherents, mostly Sunnis, accounting for 99% of the population according to a 2021 CIA ''World Factbook'' estimate, and 97.9% according to Pew Research in 2020. There are about 290,000 Ibadis in the M'zab Valley in the region of Ghardaia. Estimates of the Christian population range from 20,000 to 200,000 Algerian citizens who are Christians predominantly belong to Protestant groups, which have seen increased pressure from the government in recent years including many forced closures.