A new report from a team of Duke and UC-Berkeley researchers highlights the continuing growth in the number of Americans who indicate no religious affiliation, with a full 20% now answering “none” when asked “What is your religious preference?”

Michael Hout and Claude S. Fisher of UCB and Mark A. Chaves of Duke drew on data from the most recent General Social Survey (GSS), which has tracked religious preference since 1972, when a mere 5% of Americans self-identified as religiously unaffiliated. The report reinforces October 2012 findings by the Pew Forum on Religion & Public Life on the rapid growth in the population of Nones, especially among adults under age 30.

According to the report, the demographic tipping point in religious unaffiliation occurred in the 1990s, when the percentage of Nones grew dramatically from previous levels, jumping to 8% in 1990 and nearly doubling to 14% in 2000. Though unaffiliation tapered off slightly from 2000 to 2002—after 9/11—the robust growth trend continued, reaching 18% in 2010.

The report makes clear that the trend away from affiliation with organized religion is not an indication of declining religious belief. They write that “conventional religious belief, typified by belief in God, remains very widespread—59 percent of Americans believe in God without any doubt,” adding that, “Atheism is barely growing,” with 1% in 1962 and 3% in 2012 indicating no belief in God.

The report raises important questions about the relationship between religious affiliation, religious identity, and religiosity in general in the United States that may be addressed in future work by Hout and Fischer on generational and political factors in affiliation, perhaps more particularly, and by Chaves on “the congregational context of religious participation.”

As this work unfolds, RD readers who self-identify as one or another variety of None are invited to share their own perspectives on religion, spirituality, meaning-making, and self-realization in my Nones Beyond the Numbers narrative survey.*

*The survey results will contribute to three intertwined research projects I am currently conducting on the meaning-making practices of Nones. The first, sponsored in part through the Social Science Research Council’s “New Directions in the Study of Prayer” initiative, will explore the plurality of Nones who say they regularly engage in prayer. The second, sponsored in part through a Hackworth Grant from the Markkula Center for Applied Ethics at Santa Clara University, will explore the ethical practices of Nones. These two projects are part of a larger book project, Choosing Our Religion: The Spiritual Lives of America’s Nones, which will be released by Oxford University Press in 2014.