Editor's note: This post is part of a series by Dr. Baker on Our Values about core American values. This week Dr. Baker is discussing global religions.

Global religions are belief systems that have spread far and wide from their lands of origin. So far this week, we’ve discussed the global migration of the two biggest religions in the world, Christianity and Islam. We’ve also discussed the meanings of Christmas, the most celebrated holiday in Christianity.

Today, we take a look at the world’s third largest “religious” group— the unaffiliated. (Click the new Pew map of this group, above, to visit the Pew website and learn more.)

Sometimes the expansion of this group is described as “the rise of the Nones” in news stories—because millions of these men and women answer survey questions about religious affiliation with “None.” But the new Pew Report groups “Nones” along with people who may prefer to call themselves “Atheist” or “Agnostic.”

Together, these men and women are “unaffiliated.” Within this broad category, some people do have spiritual and religious beliefs — they just don’t identify with any specific religious group.

How large is the unaffiliated group?

There are about 1.1 billion unaffiliated in the world, accounting for 16 percent of the world’s population, according to the new Pew report.

Where do they live?

Most of these men and women live in the Asia-Pacific region, comprising more than three-quarters (76.2 percent) of all unaffiliated in the world. That’s about 21 percent of all people who live there.

Europe claims the second highest concentration, with more than 135 million unaffiliated. This amounts to 18 percent of the European population.

North America is third, with almost 60 million — about the same portion of the population as in Europe.

The regions of Sub-Saharan Africa and the Middle East/North Africa have the lowest concentrations, with only 3.2 percent and 0.6 percent of their populations, respectively, counted as unaffiliated.

While you may have seen recent news stories about growth within this group—I do want to underline that the main pattern in the Pew report is the global persistence of religion. Around the world, religion remains a potent force in the lives of most people.

Do you expect the numbers of unaffiliated to grow?

In the next decade, do you think world religions will grow? Or shrink?

Wayne Baker is a sociologist on the faculty of the University of Michigan Ross School of Business. Baker blogs daily at Our Values and can be reached at ourvaluesproject@gmail.com or on Facebook.