Demographics of Iraq
97% of Iraqis follow Islam: 61% Shia and 34% Sunni. 1% of these describe themselves as "Just a Muslim". According to the CIA Factbook, Shias make up 60% of population, while Sunnis 35%. Christianity accounts for 5%, and the rest practice Mandaeism, Yazidism and other religions.
Islam in Iran
Iran's population is about 82,000,000 people, and Islam is the religion of 99.4% of Iranians. Nearly 90% of Iranians are Shi'a and about 10% are Sunni. Most Sunnis in Iran are Kurds, Larestani people (from Larestan), Turkomen, and Baluchs, living in the northwest, northeast, south, and southeast. Almost all of Iranian Shi'as are Twelvers.