On Tuesday, Pew released a doozy of a survey on "America's changing religious landscape." The biggest change is the sharp drop in Americans who identify as Christian, from 78.4 percent in 2007 to 70.6 percent last year. Christianity's downsizing "is big, it's broad, and it's everywhere," said Alan Cooperman, Pew's director of religion research. "The decline is taking place in every region of the country, including the Bible Belt."
The sharpest declines are among mainline Protestants (14.7 percent, from 18.1 percent in 2007) and Roman Catholics (20.8 percent, from 23.9 percent), with a much smaller drop in evangelical Protestants (25.4 percent, from 26.3 percent).
Where are those Christians going? To the "nones," mostly — embracing atheism, agnosticism, vague spirituality, and indifference. The number of atheists (3.1 percent) and agnostics (4 percent) doubled, and there are more total "nones" (22.8 percent) than Catholics, or than United Methodists, Presbyterians, and Evangelical Lutherans combined. The number of non-Christian religious also grew slightly, to 5.9 percent from 4.7 percent, with most of the growth among Hindus and Muslims.
The aversion of younger people to organized Christianity is a big factor, but people in all demographics are leaving the churches. Immigration is helping bolster the numbers of most Christian denominations, but this chart from Pew offers a big piece of the puzzle:
As to why Americans are leaving Christianity, Pew doesn't say. "But the low levels of Christian affiliation among the young, well educated, and affluent are consistent with prevailing theories for the rise of the unaffiliated," says Nate Cohn at The New York Times, citing "the politicization of religion by American conservatives, a broader disengagement from all traditional institutions and labels, the combination of delayed and interreligious marriage, and economic development."
The new numbers will have a pretty marked influence on American life. Mike Hout, a demographer at New York University, tackles one political angle. "Traditionally, we thought religion was the mover and politics were the consequence," he said. Now, it's the opposite: Many evangelical Protestants and Catholics left their churches because "they saw them align with a conservative political agenda and they don't want to be identified with that."
Pew interviewed 35,071 adults from June to September 2014, and the poll has a margin of error of ±0.6 percentage points. Read more at Pew.