April 5, 2017

Christians remain world’s largest religious group, but they are declining in Europe

Christians remained the largest religious group in the world in 2015, making up nearly a third (31%) of Earth’s 7.3 billion people, according to a new Pew Research Center demographic analysis. But the report also shows that the number of Christians in what many consider the religion’s heartland, the continent of Europe, is in decline.

Christians had the most births and deaths of any religious group in recent years, according to our demographic models. Between 2010 and 2015, an estimated 223 million babies were born to Christian mothers and roughly 107 million Christians died – a natural increase of 116 million. 

But among Christians in Europe the reverse is true: Deaths outnumbered births by nearly 6 million during this brief period. In Germany alone, there were an estimated 1.4 million more Christian deaths than births from 2010 to 2015. This natural decrease in Europe’s aging Christian population was unique compared with Christians in other parts of the world and other religious groups. In fact, Muslims and the unaffiliated in Europe both experienced natural increases in their populations, with our new report estimating that there were over 2 million and 1 million more births than deaths, respectively, between 2010 and 2015.

Globally, Muslims make up the second largest religious group, with 1.8 billion people, or 24% of the world’s population, followed by religious “nones” (16%), Hindus (15%) and Buddhists (7%). Adherents of folk religions, Jews and members of other religions make up smaller shares of the world’s people.

Muslims experienced the greatest natural increase among all religious groups, including Christians. Births to Muslims between 2010 and 2015 outnumbered deaths by 152 million (213 million births vs. 61 million deaths). Globally, all major groups had more births than deaths.

Not all babies will remain in the religion of their mother, of course. In some countries, including the United States, it is fairly common for adults to leave their childhood religion and switch to another faith (or no faith). Globally, however, the effect of religious switching is overshadowed by the impact of differences in fertility and mortality.

Indeed, fertility differences between religious groups are one of the key factors behind current population trends and will be important for future growth. Globally, Muslims have the highest fertility rate of any religious group – an average of 2.9 children per woman, well above replacement level (2.1), the minimum typically needed to maintain a stable population. This fertility advantage is one reason why Muslims are expected to catch up with Christians in absolute number and as a share of the global population in the coming decades. Christians have the second highest fertility rate, at 2.6 children per woman. Hindu and Jewish fertility (2.3 each) are both just below the global average of 2.4 children per woman. All other major religious groups have fertility levels too low to sustain their populations.

Age differences are also important for future growth. Some religious groups’ adherents are predominantly young, with their prime childbearing years still ahead of them, while members of other groups are older and largely past their childbearing years. Muslims have the youngest median age (24) of all religious groups, which is also expected to contribute to their rapid growth. Hindus (27) are also younger than the median age of the world’s overall population (30), while the median age of Christians (30) matches the global median. All the other groups are older than the global median, which is part of the reason they are expected to fall behind the pace of global population growth.

Topics: Europe, Religious Affiliation, Christians and Christianity, Muslims and Islam

  1. Photo of Conrad Hackett

    is a demographer focusing on religion at Pew Research Center.

  2. Photo of David McClendon

    is a research associate focusing on religion research at Pew Research Center.


  1. Anonymous3 months ago

    The increase and decrease of faith now not depend on the birth but the truth of that faith. Christianity was forsaken by the West because of its absurduties.. people get information from internet..

  2. Anonymous3 months ago

    Religons in china are restricted, and i think if they were reported will make a big impact to this data.

  3. Anonymous4 months ago

    There is a basic fallacy here. No one is born a Christian. You might be born to Christian parents, but being a Christian takes more than that.

  4. Anonymous4 months ago

    This data at least gives a bit to be happy about. Christian decline is a devastating thing for the world, but in the overall ‘battle’ with Islam, consider this.

    The last statistic Pew had on the fertility rates of Christians and Muslims, Christians had 2.7 children per women, whereas Muslims were topping 3.2 children per women. Now, the numbers are respectively 2.6 for Christians and 2.9 for Muslims. Christians declined by 0.1, whereas Muslims declined by 0.3. The fertility rate of Muslims are going down faster than they are for Christians, which will help even things out in the future.

    As it is right now, the fertility rates in predominately Muslim countries are not predicted by Pew to fall too quickly. However, recent years of fertility statistics that can be found on Worldometers found that fertility rates in some Muslim countries are dropping like rocks. The country with the fastest declining fertility rate in the world from 2015-16 was Afghanistan, a country nearly 100% Muslim. The fertility rate dropped by .19 in a single year. The second biggest drop was in Yemen, also another country with a nearly 100% Muslim population. If my memory is correct, the drop was about as high as .13 in a single year. It seems as if the fertility rate of Muslims is dropping faster than it is for Christians, possibly by some speed as well.

    Some large Muslim countries, like Iran, have fertility rates as low as 1.7, which is almost mind boggling for a third world Muslim country. Others hopefully will catch up in due time as well.

    Currently, the fertility rate in Western (Christian) countries is actually going up overall, although still below replacement level. So, considering all this, we cant simply take the current high Islamic fertility rates to predict complete majority in the future, we must wait and see what happens.

  5. Anonymous4 months ago

    “European Dream”, by Rifkin, said Europe under the EU had the model for the future, but no population to do the model with.

    Increasingly, it is clear that the future will be up to whether the Muslim majority wants that dream or a different dream. Unless, of course, somebody like Marine Le Pen wins and change the course that Europe is on, the future of Europe is Islam. It doesn’t matter how “tolerant” you are or how much you love multiculturalism: facts are facts.

  6. Anonymous4 months ago

    Europeans need to become Biblical Christians