For centuries Christianity has been the largest organized religion in the world, especially in the United States and Western Europe. However that may soon change with Islam and people with no religious affiliation are consistently growing, inching closer and closer to Christianity year after year.
As far as worldwide religious growth is concerned Islam is the fastest growing religion with over 1.6 billion adherents, almost a third of the global population. Over half of the world’s muslim populations are from Eastern Asia, specifically India and Indonesia. The next biggest chunk of muslims, over 300 million people, hail from the Middle East and Northern Africa. Sub Saharan Africa is home to over 200 million muslims and Europe is home to an ever growing Islamic community almost 50 million strong.
The global Muslim population is far reaching and widespread, it is made up of over a billion people with unique views, and it is growing quickly, but people not affiliated with any religion is growing too. Sometimes even faster.
People who claim to be “non affiliated” come from various groups of people with various structures of thought. By and large though they are secular, atheists or agnostics, in the United States and Western Europe. These people represent the fastest growing “religious community” but they also represent a fairly small minority of people, at least on the global scale. People unaffiliated with any religion are the 3rd largest group in the world according to Pew Research, representing 1.1 billion people worldwide. Over 600 billion of those people are from China and a small percentage of them are self described atheists.
In 2014 atheists represented 7% of the American religious landscape. Almost double the 4% figure in 2010. Atheists and agnostics are a rapidly growing group, along with people not affiliated with a religion in general. But those are two different groups, albeit with a significant amount of overlap.
Worldwide the nonaffiliated population is largest in China, but the atheist or agnostic community although smaller, is quickly growing. Especially in countries like the United States. Overall Islam is the fastest growing religion in the world and it does not have the same issues in regards to splintering into separate demographic groups. Regardless, the religious landscape worldwide is changing rapidly.