Jonathan Rothwell has a piece in the New York Times that tries to explain why the income of the top 1 percent has taken off in recent years. David Leonhardt had a similar piece in August. Both Rothwell and Leonhardt cite Piketty-Saez-Zucman (PSZ) data to substantiate their claims about rising top 1 percent income, but neither mention that, in the PSZ dataset, all increases in top 1 percent income since 2000 came from capital income not labor income.

Rothwell’s preferred theory for why top incomes have increased so much is that regulations have driven up the labor incomes of a small class of top earners:

Almost all of the growth in top American earners has come from just three economic sectors: professional services, finance and insurance, and health care, groups that tend to benefit from regulatory barriers that shelter them from competition.