A 2012 survey found that 36% of the world population is not religious and that between 2005 and 2012 world religiosity decreased by 9 percentage points. The Pew global report in 2010 noted that many that are not religious have some religious beliefs and the majority of nonreligious come from Asia and the Pacific. According to one source, it has been estimated that 40–50% of non-religious people hold belief in at least one deity, or in some higher power.[need quotation to verify]
Most Western democracies protect the freedom of religion, and it is largely implied in respective legal systems that those who do not believe or observe any religion are allowed freedom of thought.
A noted exception to ambiguity, explicitly allowing non-religion, is Article 36 of the Constitution of the People's Republic of China (as authored in 1982), which states that "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 who believe in, or do not believe in, any religion." Article 46 of China’s 1978 Constitution was even more explicit, stating that "Citizens enjoy freedom to believe in religion and freedom not to believe in religion and to propagate atheism."
Although 10 countries listed below have non-religious majorities, it does not mean that majority of the populations of these countries don′t belong to any religious group. For example, 67.5% of the Swedish population belongs to Lutheran Christian Church, while 58.7% of Albanians declare themselves as Muslims. Also, though Scandinavian countries have among the highest measures of nonreligiosity and even atheism in Europe, 47% of atheists who live in those countries are still members of the national churches. 
Gallup Religiosity Index 2009 (light color indicates religious, dark nonreligious)[dead link]
The tables below order the percentage of a countries population that are nonreligious from highest to lowest.
^Zuckerman, Phil, ed. (2010). "Ch. 9 Atheism And Secularity: The Scandinavian Paradox". Atheism and Secularity Vol.2. Praeger. ISBN0313351813.
^The Religiosity Index is a measure of the importance of religion for respondents and their self-reported attendance of religious services. For religions in which attendance at services is limited, care must be used in interpreting the data. (Gallup WorldView)