By the middle of this century, the number of Muslims worldwide will roughly equal those of Christians and by the century's end will exceed them, making Islam the world's largest religion.
That's according to projections in a new analysis by the Pew Research Center, which identifies Islam as the world's fastest-growing religion, owing to higher fertility rates and the fact Muslims have the youngest median age of all religious groups.
In 2010, 1.6 billion Muslims accounted for 23.2 percent of the total world population; Pew says that proportion could grow to 29.7 percent by 2050, and to 34.9 percent by 2100. By contrast Christians comprised 31.4 percent of the population in 2010, and will account for about 33.8 percent in 2100, Pew projects.
Current demographic trends indicate that the Muslim population will soar by 73 percent between 2010 and 2050, compared to an increase of 35 percent for Christians – which is in line with overall global population growth over that period – 34 percent for Hindus and 16 percent for Jews.
Also by 2050, the size of the Muslim community in the United States will have doubled in size – albeit only from one to 2.1 percent of the population; while the estimated size of the Muslim population in Europe will be ten percent by mid-century.
Each Muslim woman has an average of 3.1 children, compared to 2.7 children for Christian women, and an average of 2.3 children for all non-Muslim women. The median age of Muslims in 2010 was 23, compared to 30 for all non-Muslims. The patterns could have a significant impact in some countries with large Muslim populations.
In Nigeria, for instance, Muslims today account for about 50 percent of the country's 155 million population, but by 2050 that is expected to rise to 58.5 percent, bringing new pressures in a country already fractured along religious lines.
Shari'a is already implemented in 12 of the country's 36 states, all in the north, the part of Nigeria where Boko Haram is conducted a bloody jihad against Christians. Pew projects that India could surpass Indonesia in 2050 as the nation boasting the largest Muslim population.
Indonesia is the world's fourth-most populous country, and an estimated 87 percent of its current population of 258 million (or some 225 million people) are Muslims, according to the CIA World Factbook.
Today, Indian Muslims comprise a minority of just 14.4 percent, but in the world's second-most populous country (1.26 billion), that amounts to around 176 million people.
By 2050, Pew says, Muslim birthrates are expected to expand the Muslim proportion of the population to 18.4 percent. Taking into account India's projected overall population growth, that will take the size of the Indian Muslim population to about 311 million.
Pakistan's Muslim population, too, is likely by 2050 to overtake that of Indonesia, which will move into third place. A large majority of the world's Muslims live in Asia rather than in the Middle East and North Africa. The world's biggest Muslim populations are, in order, in Indonesia, India, Pakistan, Bangladesh, Nigeria, Egypt, Iran and Turkey.