Excerpt from Pew Forum on Religion and Public Life  report “Nones” on the rise.
Some Evidence of Decline in Religious Commitment in the U.S. Public
The continued growth of the religiously unaffiliated is one of several indicators suggesting that the U.S. public gradually may be growing less religious. To be sure, the United States remains a highly religious country – particularly by comparison with other advanced industrial democracies – and some measures of religious commitment in America have held remarkably steady over the years. The number of Americans who currently say religion is very important in their lives (58%), for instance, is little changed since 2007 (61%) and is far higher than in Britain (17%), France (13%), Germany (21%) or Spain (22%).8  And over the longer term, Pew Research surveys find no change in the percentage of Americans who say that prayer is an important part of their daily life; it is 76% in 2012, the same as it was 25 years ago, in 1987.
But on some other key measures, there is evidence of a gradual decline in religious commitment. In 2003, for instance, 25% of U.S. adults indicated they seldom or never attend religious services. By 2012, that number had ticked up 4 points, to 29%.
Similarly, the percentage of Americans who say they never doubt the existence of God has fallen modestly but noticeably over the past 25 years. In 1987, 88% of adults said they never doubt the existence of God. As of 2012, this figure was down 8 percentage points to 80%.
9  And based on analysis of GSS data, Mark Chaves of Duke University has found that Americans born in recent decades are much less likely than their elders to report having attended religious services weekly at age 12. Young adults are also less likely than older adults to report that when they were growing up, their parents attended religious services regularly.