John Hagel writes,

the Shift Index focuses on return on assets (ROA) for all public companies in the US since 1965. The bottom line: ROA has collapsed by more than 75% over this period.

Thanks to Patri Friedman for the pointer. Hagel links to a the complete study (a book-length PDF file) that includes various nuggets. Some examples:

The “topple rate” at which big companies lose their leadership positions has more than doubled, suggesting that “winners” have increasingly precarious positions.

Hagel’s Big Shift reminded Patri of my Great Recalculation.

Along those lines, I think that one can draw a trend line from, say, 1995 to 2015, and the current recession will not be a major factor in that line. Yes, the unemployment rate is dramatically higher during the recession. But my guess is that if you look at income gains relative to skill sets and temperaments (Hagel has some interesting things to say about temperament), my guess is that they will be dominated by the trend, not by the cycle. My guess is that 2004-2006 was a delay period, and 2008-2009 was an acceleration period for these trends, but overall the period 1995-2015 is one of sharp depreciation of some forms of human capital and dramatic appreciation of other forms of human capital. (My chosen endpoints of 1995 and 2015 are arbitrary. Do not read much into the specific dates.)