It can be difficult to find research on religiosity on a global scale, particularly where atheism and irreligion are included as distinct categories. But the statistics are out there. Here is a view of the world in a survey taken by WIN-Gallup International, published in 2012 under the title "Global Index of Religiosity and Atheism".
How much of the world is religious? The survey puts the number at 59% religious, 23% not-religious and 13% convinced-atheist. Religious outnumber the non-religious and atheists by just 9% overall.
Encouragingly, that 9% lead is shrinking overall. Since 2005, Religiosity has dropped by 9% while atheism has risen 5%. If this continues, religious will dip below 50% and become a global minority in under ten years.
Other interesting findings:
- The number of atheists in the United States and the Kingdom of Saudi Arabia are both found to be 5%. (I'm delighted that some in KSA are alarmed at this finding and call atheism a "cancer".)
- Education and higher incomes are less associated with religion; ignorance and poverty are more associated with religion.
- Religious are a minority (under 50%) in countries including; Ireland, Australia, Austria, Azerbaijan, Iceland, Netherlands, France, Czech Republic, Sweden, Canada, Japan, Turkey, Vietnam and China.
- Religious are nearly a minority (55% or under) in countries including; Switzerland, Spain, Russian Federation, Finland, Germany, and South Korea
- Female atheists outnumber male atheists by 14% to 12%. Male religious outnumber female religious by 60% to 57%. (I don't find this surprising considering women are treated rather poorly in the tenets of the major religions.)