U.S. economist Robert Gordon predicts that the next 20 years will be the slowest period of growth in U.S. history.

Why?

Four reasons. First, the retirement of the baby boomers means more Americans won't be contributing productively to the economy. Instead, they'll be living off savings and social welfare. Second, the turbo boost of the Internet is over, and we shouldn't expect workers to pick up productivity enough to compensate for the dead-weight boomers. Third, education levels have flat-lined, which is putting the breaks on productivity. Fourth, slow productivity gains will contribute to slowly rising income and living standards (GDP per person), which will make it all the harder to pay back our debt or fix our problems.

Peter Coy passes along this chart to illustrate the point:

gdp growth productivity.png

I think Robert Gordon is wonderful (his work on jobless recoveries is especially insightful), but I'd caution against even the most sober-sounding 20 year growth projections. In the late 1970s, we were worried about inflation and the Japan overtaking the United States in domestic production. By 1999, Japan was halfway through its Lost Decades and we were riding the longest economic expansion in history. In 1999, the United States was worried about government surpluses hurting the economy. Today we're worried that our deficit crisis is politically unsolvable.

A lot can change in 20 years. It always does.

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