Nigeria has one of the largest Muslim populations in West Africa, with the Pew Research Center estimating that it is between 48.5% (2010) and 50.4% (2009). The CIA estimates 50% while the BBC estimates slightly over 50% (2007). Muslims in Nigeria are predominantly Sunni in the Maliki school, which is also the governing Sharia law. However, there is a significant Shia minority, primarily in Kaduna, Kano, Katsina and Sokoto State; (see Shia in Nigeria). A smaller minority follow the Ahmadiyya, a reformatory religion originating in 19th century India. In particular Pew Forum on religious diversity identifies 3 s Shia Muslims and 12 percent as 'Darika' Muslims.