850,000,000 Secularists, Non-Religious, Agnostic and Atheists in the world. That's about 15% or more than 1 out of 10 people, making this the fourth largest religious belief grouping.
The population of non-believers in the USA is about 10% and 10-25% in Europe.
Most studies of the hightly educated and scientists show a higher proportion of atheists and non-believers.
Prison populations appear to have a lower proportion of Atheists and non-believers.
Statistics of Atheists are generaly considered statisticaly low especially in 'self-identification' surveys because many who are technically 'Atheists' shy away from the term, often using 'non-religious', 'agnostic', 'secular' or 'humanist' due to Atheism's negative perception.
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