The growth in the unaffiliated is clearly coming at the expense of Protestants, whose decline mirrors the unaffiliated increase. The generational gap in the findings is also quite striking. Thirty-two percent of young adults 18-29 years of age now identify themselves as unaffiliated, in contrast to only 9% of those age 65 and over.
MORE: http://www.americanhumanist.org/HNN/details/2012-10-pew-survey-reveals-religions-fading-influence