Looking at the numbers, two features immediately jump out. First, the proportion of white Christians (including Protestants and Catholics) in the country, while still comprising the largest single wedge in the pie chart, has slipped below a majority to 47 percent. Moreover, if that measure is restricted to include only the direct descendants of white Christian America—white mainline Protestants and white evangelical Protestants—the number decreases to only 32 percent of Americans. Second, the religiously unaffiliated—a group that is growing rapidly—comprise more than one in five Americans today.

The next chart digs deeper into these numbers and provides some insight into what the future may hold. Like an archaeological excavation, the chart sorts Americans by religious affiliation and race, stratified by age—demonstrating at a glance the decline of white Christians among each successive generation. This snapshot uncovers a striking finding: Today, young adults, ages 18 to 29, are less than half as likely to be white Christians as seniors. Nearly seven in 10 American seniors are white Christians, compared to fewer than three in 10 young adults. Although the declining proportion of white Christians is due in part to large-scale demographic shifts, this chart also highlights the other major force of change in the religious landscape: young adults’ rejection of organized religion.