According to the INSEE, between 4 and 5 million French residents were born or had at least one parent born in a predominantly Muslim country, particularly Algeria, Morocco and Tunisia. An IFOP survey in 2008 reported that, of immigrants from these predominantly Muslim countries, 25 percent went to the mosque regularly; 41 percent practised the religion, and 34 percent were believers but did not practice the religion. In 2012 and 2013, it was estimated that there were almost 500,000 Muslims in the City of Paris, 1.5 million Muslims in the Île-de-France region and 4 to 5 million Muslims in France.