In the last five years alone, the unaffiliated have increased from just over 15% to just under 20% of all U.S. adults. Their ranks now include more than 13 million self-described atheists and agnostics (nearly 6% of the U.S. public), as well as nearly 33 million people who say they have no particular religious affiliation (14%)
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One important factor behind the growth of the religiously unaffiliated is generational replacement, the gradual supplanting of older generations by newer ones. Among the youngest Millennials (those ages 18-22, who were minors in 2007 and thus not eligible to be interviewed in Pew Research Center surveys conducted that year), fully one-third (34%) are religiously unaffiliated, compared with about one-in-ten members of the Silent Generation (9%) and one-in-twenty members of the World War II-era Greatest Generation (5%). Older Millennials (ages 23-30) also are substantially less likely than prior generations to be religiously affiliated.
But generational replacement is not the only factor at play. Generation Xers and Baby Boomers also have become more religiously unaffiliated in recent years. In 2012, 21% of Gen Xers and 15% of Baby Boomers describe themselves as religiously unaffiliated, up slightly (but by statistically significant margins) from 18% and 12%, respectively, since 2007. The trend lines for earlier generations are essentially flat. Not only are young adults less likely to be affiliated than their elders, but the GSS shows that the percentage of Americans who were raised without an affiliation has been rising gradually, from about 3% in the early 1970s to about 8% in the past decade. However, the overwhelming majority of the “nones” were brought up in a religious tradition. The new Pew Research Center/Religion & Ethics NewsWeekly survey finds that about three-quarters of unaffiliated adults were raised with some affiliation (74%).
MORE: http://www.pewforum.org/Unaffiliated/nones-on-the-rise.aspx
See also...
New Report Finds One-in-Five Adults Have No Religious Affiliation
http://www.pewforum.org/Press-Room/Press-Releases/%E2%80%9CNones%E2%80%9D-on-the-Rise--New-Report-Finds-One-in-Five-Adults-Have-No-Religious-Affiliation.aspx
Pew: 20% of Americans Are Now Atheist, Agnostic or Unaffiliated With a Religion
http://www.theblaze.com/stories/pew-20-of-americans-are-now-atheist-agnostic-or-unaffiliated-with-a-religion/
Study: Protestants no longer a majority in U.S.
http://www.cbsnews.com/8301-201_162-57529286/study-protestants-no-longer-a-majority-in-u.s/?tag=categoryDoorTopNews;catDoorTopNews
One in five Americans reports no religious affiliation, study says
http://www.washingtonpost.com/local/one-in-five-americans-reports-no-religious-affiliation-study-says/2012/10/08/a7599664-11c8-11e2-855a-c9ee6c045478_story.html?hpid=z1
Humanists Recognize Increasing Number of "Nones" as Feeding Secular Movement's Growth
http://www.americanhumanist.org/news/details/2012-10-humanists-recognize-increasing-number-of-nones-as-fe
Survey: One in five Americans has no religion
http://religion.blogs.cnn.com/2012/10/09/survey-one-in-five-americans-is-religiously-unaffiliated/?hpt=hp_c2
Are Americans Becoming Less Religious?
http://www.foxcharlotte.com/news/local/Are-Americans-Becoming-Less-Religious-173422271.html
