According to the Religion News Service, a 2011 Pew survey shows that roughly 19% of U.S. residents polled described their religious affiliation as "none." This is the highest percentage ever recorded by the organization.
What strikes me as even more noteworthy than the gradual increase in this number is that it appears to be trending upward while many Christian denominations are either flat or in decline. These trends are certainly encouraging, even if they are slower than most of us would like.
The report brings up a good point about how the number of "nones" is unlikely to rise too much given differences in birth rate. As we know, some religious groups are encouraged to have as many children as possible (e.g., Catholics and Mormons). It is clear that these groups are going to have more children than most atheist couples.
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