Bryce Bartlett, a PhD candidate in sociology and trainee in the demography of aging, along with his coauthor, Cyrus Schliefer received an award at the Population Association of America's 2016 annual meeting for their poster: "Projecting Religious Switching in America: A Bayesian Cohort Component Approach." Using the General Social Survey Panels 2006-2014, they estimate rates of religious switching, mortality, and fertility, and simulate changes in proportions of religious affiliation into the future.
Their study finds declines in all religious affiliations, except for those professing no religious affiliation (Nones), which is projected to grow between 31% and 43% in the coming decades. This growth in the Nones is primarily due to higher rates of religious switching in young adulthood, which outweighs higher fertility rates among Evangelicals and Catholics. They also find; however, that at older ages, Nones become increasingly more likely to join (or rejoin) a religious tradition.