Bangladesh followed by 86.6 percent of the population. The country is home to most Bengali Muslims, the second-largest ethnic group in the Muslim world. Most Bangladeshi Muslims are Sunni, followed by Shia and Ahmadiya. About four percent are non-denominational Muslims. Bangladesh has the fourth-largest Muslim population in the world, and is the third-largest Muslim-majority country (after Indonesia and Pakistan). Sufism has a lengthy heritage in the region. The largest gathering of Muslims in Bangladesh is the Bishwa Ijtema, held annually by the Tablighi Jamaat. The Ijtema is the second-largest Muslim congregation in the world, after the Hajj. Hinduism is followed by
Muslim population growth Muslims. According to Pew Research, religious conversion has no net impact on the Muslim population as the number of people who convert to Islam is roughly similar to those who leave Islam. It is often reported from most recent various sources in 2010, including the German domestic intelligence service, that Salafism is the fastest-growing Islamic movement in the world. Though according to the "World Christian Encyclopedia", published in 2001, the fastest-growing branch of Islam is Ahmadiyya. However, many Muslims consider Ahmadi Muslims as either "kafirs" or heretics.<ref> Muslim population growth Muslim population growth refers to the topic of population growth