Christianity

One-in-five immigrants identified themselves as unaffiliated in 2014, an increase of 4 percentage points from the 16% who said so in 2007.

In recent years, the share of Americans who identify with mainline Protestantism has been shrinking significantly, a trend driven partly by generational change.

One big reason evangelical Protestants have not declined at the same rate as other major Christian groups is that they are gaining new converts at a greater rate than they are losing people who were raised in the tradition.

Explore the geographic distribution and demographics of America's major religious groups.

The number of Christians in Europe is forecast to drop by about 100 million by 2050, while the share of Muslims and smaller religious minorities will increase.

If current demographic trends hold, by 2050, Muslims are projected to be more numerous in the U.S. than people who identify as Jewish on the basis of religion.

The share of the world's Christians in Europe will continue to decline while the percentage in sub-Saharan Africa will increase dramatically.

What will the world’s religious landscape look like a few decades from now?

As of 2010, nearly a third of the world's population identified as Christian. But if demographic trends persist, Islam will close the gap by the middle of the 21st century.