The Constitution of the Republic of China protects people's freedom of religion and the practices of belief. There are approximately 18,718,600 religious followers in Taiwan as of 2005 (81.3% of total population) and 14–18% are non-religious. According to the 2005 census, of the 26 religions recognized by the ROC government, the five largest are: Buddhism (8,086,000 or 35.1%), Taoism (7,600,000 or 33%), I-Kuan Tao (810,000 or 3.5%), Protestantism (605,000 or 2.6%), and Roman Catholicism (298,000 or 1.3%). But according to the CIA World Factbook and other latest sources from US State Department or the Religious Affairs Section of the MOI, over 93% of Taiwanese are adherents of a combination of the polytheistic ancient Chinese religion, Buddhism, Confucianism, and Taoism; 4.5% are adherents of Christianity, which includes Protestants, Catholics, and other, non-denominational, Christian groups; and less than 2.5% are adherents of other religions, such as Islam. Taiwanese aborigines comprise a notable subgroup among professing Christians: "...over 64 percent identify as Christian... Church buildings are the most obvious markers of Aboriginal villages, distinguishing them from Taiwanese or Hakka villages."