December 18, 2012 (ndtv.com): (HPI note: This report is on the same study cited above, but with a different focus.) 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
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.