This blog is intended to go along with Population: An Introduction to Concepts and Issues, by John R. Weeks, published by Cengage Learning. The latest edition is the 13th (it will be out in January 2020), but this blog is meant to complement any edition of the book by showing the way in which demographic issues are regularly in the news.

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Saturday, April 8, 2017

Globally Muslims Growing Faster Than Christians

Pew Research has a new report out projecting the global growth of population by religious affiliation:
While the world’s population is projected to grow 32% in the coming decades, the number of Muslims is expected to increase by 70% – from 1.8 billion in 2015 to nearly 3 billion in 2060. In 2015, Muslims made up 24.1% of the global population. Forty-five years later, they are expected to make up more than three-in-ten of the world’s people (31.1%).
Westerners tend to think of Muslims in terms of the Middle East, but the Pew projections suggest that Indonesia will continue to be the most populous Muslim nation in the world, and that the second largest population of Muslims will be in India, despite their continuing to be a minority in that Hindu-majority nation.

You should be able to figure out the reason for the fact that Muslims will outnumber Christians by mid-century. It's fertility. Muslim women have more children on average than non-Muslim women (see graph below), and the younger age structure of Muslim nations means that there are many more women of childbearing age having those numerous children. 


  1. Hi John,
    Most current conflicts with the death tolls are located in the Muslim world. Given that Total Population in an Area = Fertility - Mortality +/- Migration, how does this research account for death, especially death resulting from conflict? My assumption here is that faith does not change with migration. Thanks,

    1. The Pew Research projections take into account the differing mortality and migration levels, so even when those are accounted for, it is the higher fertility among Muslims that makes the difference.