If demographics truly are destiny, the world is destined to have nearly as many Muslims as Christians, fewer Buddhists, and a declining share of agnostics and atheists by the year 2050, according to a new demographic survey from Pew Research.
Between 2010 and 2050, Pew expects the global population to rise 35 percent to 9.3 billion people. During this period of global growth, the Muslim population will grow 73 percent, owing to "comparatively youthful populations with high fertility rates." The number of Christians will also rise, but at a slower 35 percent rate that keeps pace with the overall trend in global population growth.
The religion with the worst growth prospects is Buddhism, which is the only faith that Pew expects to actually lose adherents in absolute numbers by 2050.
Interestingly, Pew is projecting that agnostics, atheists, and those not formally aligned with any religion will lose share globally by 2050, falling from 16 percent of the global population in 2010 to 13 percent in 2050, despite a growth in absolute numbers. The relative decline of a group typically associated with modernization reflects the "vivid geographic differences in the patterns of religious growth in the coming decades," Pew noted.
"Religions with many adherents in developing countries - where birth rates are high, and infant mortality rates generally have been falling - are likely to grow quickly," Pew wrote. "Much of the worldwide growth of Islam and Christianity, for example, is expected to take place in sub-Saharan Africa. Today's religiously unaffiliated population, by contrast, is heavily concentrated in places with low fertility and aging populations, such as Europe, North America, China and Japan."
Muslims win the baby-making race, with a global fertility rate of 3.1 children per woman. Christians come in second, producing 2.7 children per woman while Hindus place third with 2.4 children per woman.
The report also studies how the net age of a given population and global migration patterns will impact religious rates. What Pew did not take into account was whether economic modernization would alter the growth of religious identity. While the study acknowledges that economic growth has been cited to explain why North America and Europe have a higher percentage of atheists and agnostics, the authors discount this as a factor when making their global projections, pointing out that Indians, for instance, have retained their affiliation to Hinduism despite rapid social and economic growth.