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First, if you’re trying to make sense of the stock market, I discuss its gyrations on the new episode of the Slate Political Gabfest, with Emily Bazelon, John Dickerson and David Plotz.

Census ‘sabotage.’ “It is hard to exaggerate the importance of a successful decennial census for municipalities across our nation,” reads the first sentence of a letter sent to the Trump administration yesterday by a bipartisan group of 161 mayors.

The census is a more important part of national life than many people realize. It determines how many congressional representatives each state gets and helps determine how federal funding is distributed. Census data are also vital to many businesses and academic researchers.