A comprehensive demographic study of more than 230 countries and territories conducted by the Pew Research Center’s Forum on Religion & Public Life estimates that there are 5.8 billion religiously affiliated adults and children around the globe, representing 84% of the 2010 world population of 6.9 billion.
The demographic study – based on analysis of more than 2,500 censuses, surveys and population registers – finds 2.2 billion Christians (32% of the world’s population), 1.6 billion Muslims (23%), 1 billion Hindus (15%), nearly 500 million Buddhists (7%) and 14 million Jews (0.2%) around the world as of 2010.
Roughly one-in-six people around the globe (1.1 billion, or 16%) have no religious affiliation. This makes the unaffiliated the third-largest religious group worldwide, behind Christians and Muslims, and about equal in size to the world’s Catholic population.
The religiously unaffiliated include atheists, agnostics and people who do not identify with any particular religion in surveys. However, many of the religiously unaffiliated have some religious beliefs. For example, belief in God or a higher power is shared by 7% of Chinese unaffiliated adults, 30% of French unaffiliated adults and 68% of unaffiliated U.S. adults. Some of the unaffiliated also engage in certain kinds of religious practices. For example, 7% of unaffiliated adults in France and 2 7% of those in the United States say they attend religious serv ices at least once a year. And in China, 44% of unaffiliated adults say they have worshiped at a graveside or tomb in the past year
The WIN-Gallup International ‘Religiosity and Atheism Index’ which measures global self-perceptions on beliefs is based on interviews with more than 50,000 men and women selected from 57 countries across the globe in five continents. The survey also provides trend data for shifts in attitudes since 2005.
Interesting Gallup Results
RELIGIOSITY IS HIGHER AMONG THE POOR: People in bottom income groups are 17% more religious than those in top income groups. (49% of highest fifth quintile group versus 66% of the bottom quintile)
RELIGIOSITY IS LOWER AMONG COLLEGE EDUCATED: College educated are 16% less religious than those without secondary education.
TRENDS SINCE 2005: Religiosity drops by 9%, while atheism rises by 3%. Religiosity Index dropped by 9% during these seven years. Most of the shift is not drifting from their faith, but claiming to be ‘not religious’ while remaining within the faith.
This suggests that if everyone were financially over $50,000 per capita PPP GDP and had college education then religiosity would be a minority of the global population.
The US went from 1% athiest in 2005 to 5% athiest in 2012.
Gallop 13% athiest would mean that athiest is a global number 4 after christianity, muslim and hindu.
Some other Pew Surveys
In recent years, Pew Research surveys have found evidence of a gradual decline in religious commitment in the U.S. public as a whole. For example, there has been a modest uptick over the past decade in the share of U.S. adults who say they seldom or never attend religious services. The number of Americans who do not identify with any religion also has grown in recent years; indeed, about one-fifth of the public overall – and a third of adults under age 30 – are religiously unaffiliated as of 2012. Fully a third of U.S. adults say they do not consider themselves a “religious person.” And two-thirds of Americans – affiliated and unaffiliated alike – say religion is losing its influence in Americans’ lives.
Growth of Unaffiliated in the USA and the USA breakdown