Brad Wright, a professor of sociology at UMass, observes something that might be surprising about growth in the Nones — read the whole article:
Once again, the percentage of being unaffiliated increased in each group, but relatively speaking, it’s increased most among the middle-aged and the elderly. In both the percentage of the unaffiliated more than tripled, compared to the 2.5x increase in the young. There is some lagged effect, as the elderly are catching up the middle-aged in the past decade, but overall, the rise of the religious nones is something that spans all age groups. Thus it’s a societal-wide change more than just an age or generational change.