I haven’t read Tyler’s much-discussed e-book, but he defended the main theses over a few lunches.  My prediction: When I get around to reading the book, my reaction to the numbers will mimic Brink Lindsey’s:

Tyler correctly points out that median family income rose smartly
after World War II only to fall off sharply in the ’70s… Between 1950 and 1973, the
average annual growth rate of real GDP per capita was 2.5%; for the
period between 1973 and 2007, the corresponding figure was only 1.9%

But look what happens when you put these figures in larger
historical context (note: I’m using calculations by Angus Maddison for
earlier periods and Census figures for post-WWII periods):

1820 – 1870            1.3%

1870 – 1913            1.8%

1913 – 1950            1.6%

1950 – 1973            2.5%

1973 2007              1.9%

From this broader perspective, what Tyler calls the Great Stagnation
looks like a return to normalcy after the “Great Boom” of the post-WWII
decades. Indeed, recent growth rates are better than those of all other
earlier periods. So yes, growth has cooled down since the postwar
“Golden Age,” and that fact poses real economic and political
challenges. But the Golden Age was the outlier, not our present era; it
just doesn’t make sense to talk about the present period as stagnant
after centuries of easy growth.

On a deeper level, I’m baffled why Tyler would focus on slight declines in American growth when the world just had the best decade ever.  Finding dark linings in silver clouds is work for lesser men.

HT: Tyler himself