China has the world's greatest irreligious population. The Chinese government is officially atheist. Despite limitations on certain forms of religious expression and assembly, religion is not banned, and religious freedom is nominally protected under the Chinese constitution. Among the general Chinese population, there are a wide variety of religious practices. The Chinese government's attitude to religion is one of skepticism and non-promotion. According to a 2012 Gallup poll, 47% of Chinese people were convinced atheists, and a further 30% were not religious. In comparison, only 14% considered themselves to be religious. More recently, a 2015 Gallup poll found the number of convinced atheists in China to be 61%, with a further 29% saying that they are not religious compared to just 7% who are religious. Since 1978, the constitution provides for religious freedom: "No state organ, public organization or individual may compel citizens to believe in, or not to believe in, any religion; nor may they discriminate against citizens because they do, or do not believe in religion" (article 36). The Chinese state officially recognizes five religions: Buddhism, Taoism, Islam, Catholicism, and Protestantism. In order to be a member of the Communist Party of China an individual must not have religious affiliation.