Like others, I would attribute the rise to immigration. I'm not knocking immigrants, it's just that we've had tens of millions in the last few years from all over the world and for many different reasons many of them probably couldn't (or wouldn't) satisfy the test as given.
I'm not exactly sure that the bulk of illegal immigrants would be in a position to even register in this study.
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There are no weapons of mass destruction in Iraq, Chuck Norris lives in Houston.
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