Healthcare.gov enrollment came in well below what was anticipated last month. After running very slightly ahead of last year’s numbers in December, January brought the news that about 400,000 fewer people had enrolled on the federal exchanges than did so in 2016. Those are scary numbers, not so much for the absolute size of the decline—it’s roughly 4%—but because any backwards movement is very bad news for the exchanges. Trump was only president for a few days’ worth of open enrollment. Could he really have somehow caused 400,000 people to forgo health insurance?

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