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First, I’ve spent some time recently trying to figure out just how much bigger big business in the United States has become. It turned out to be a more difficult project than I expected — which also made it more interesting.

Given the federal judge’s decision last week to allow the AT&T-Time Warner merger, I thought this was a good week to write about the project. In my column today, you’ll find two charts that show what’s happened over the last quarter-century.

The short version: Small businesses in the United States used to employ more people combined than big businesses. That’s no longer the case, and it’s a major reason why income growth has been so slow for most families and inequality has soared.