The largest religion in Thailand is Buddhism, which is practiced by approximately 94% of the population. The Thai Constitution does not indicate any state religion, but promotes Buddhism while guaranteeing religious freedom for all Thai citizens. In addition to Buddhism, Thai law officially recognizes five religions: Islam, Hinduism, Sikhism, and Christianity. Muslims make up about 4% of the population, and there is a significant Muslim population in the southern regions of Thailand. Christians, mainly Catholics, represent just over 1% of the population. Other religious groups, such as Tai folk religions and small groups of Hindus, Sikhs, and believers of Confucius Ethics, are also present in Thailand, but their numbers are quite small. According to the 2015 Gallup International survey, Thailand was the most religious country of the 65 countries polled, with 94% of Thais identifying as religious.