Via Josh Barro’s twitter feed, I ran across a paper that concludes that “the ‘historic lows’ in labor’s share [of national income] are observed only in the nonfarm business sector series produced by the Bureau of Labor Statistics. Other measures of labor’s share—for example, for the nonfinancial corporate business sector or the macroeconomy more broadly—are currently near their averages over the last several decades.”
Update: It’s an old paper, looking at the historic low measured at this point in the last economic cycle. Hope someone takes a new look.