People with no religious affiliation make up the third-largest global group in a new study of the size of the world’s faiths, placing after Christians and Muslims and just before Hindus.
The study, based on extensive data for the year 2010, also showed Islam and Hinduism are the faiths mostly likely to expand in the future while Jews have the weakest growth prospects.
It showed Christianity is the most evenly spread religion, present in all regions of the world, while Hinduism is the least global with 94 percent of its population in one country, India.
Overall, 84 percent of the world’s inhabitants, which it estimated at 6.9 billion, identify with a religion, according to the study entitled “The Global Religious Landscape” issued by the Pew Forum on Religion and Public Life on Tuesday.
Judaism, which has 14 million adherents or 0.2 percent of the world population, has the highest median age at 36, meaning its growth prospects may be weakest.
The authors noted that Israel, which has 40.5 percent of the world Jewish population, had a younger age structure than the United States, where 41.1 percent of the world’s Jews live.
The “unaffiliated” category covers all those who profess no religion, from atheists and agnostics to people with spiritual beliefs but no link to any established faith.
“Many of the religiously unaffiliated do hold religious or spiritual beliefs,” the study stressed.
“Belief in God or a higher power is shared by 7 percent of unaffiliated Chinese adults, 30 percent of unaffiliated French adults and 68 percent of unaffiliated U.S. adults,” it said.
Exact numbers for religious populations are impossible to obtain and estimates for the size of the larger faiths can vary by hundreds of millions. This study by the Washington-based Pew Forum appears to be one of the most extensive to date.