Pew Research Center found that 71% of Americans identified as Christian in 2014 — down from 78% in 2007.
In the same period, Americans identifying as having no religion grew from 16% to 23%. About 5 million less Americans now identify as Christian compared to when the study was conducted in 2007.
In the South, those not-affiliated with religion — or as the researchers call them, "nones" — rose to 19% of the population, while in the Northeast they climbed to 25%.
In the West "nones" are a larger group than any religion, making up 28% of the public.
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