Dean Baker — How Much Unemployment Was Caused by Reinhart and Rogoff's Arithmetic Mistake?

That's the question millions will be asking when they see the new paper by my friends at the University of Massachusetts, Thomas Herndon, Michael Ash, and Robert Pollin. Herndon, Ash, and Pollin (HAP) corrected the spreadsheets of Carmen Reinhart and Ken Rogoff. They show the correct numbers tell a very different story about the relationship between debt and GDP growth than the one that Reinhart and Rogoff have been hawking.

Just to remind folks, Reinhart and Rogoff (R&R) are the authors of the widely acclaimed book on the history of financial crises, This Time is Different. They have also done several papers derived from this research, the main conclusion of which is that high ratios of debt to GDP lead to a long periods of slow growth. Their story line is that 90 percent is a cutoff line, with countries with debt-to-GDP ratios above this level seeing markedly slower growth than countries that have debt-to-GDP ratios below this level. The moral is to make sure the debt-to-GDP ratio does not get above 90 percent.

There are all sorts of good reasons for questioning this logic....
But HAP tells us that we need not concern ourselves with any arguments this complicated. The basic R&R story was simply the result of them getting their own numbers wrong.

After being unable to reproduce R&R's results with publicly available data, HAP were able to get the spreadsheets that R&R had used for their calculations. It turns out that the initial results were driven by simple computational and transcription errors....
This is a big deal because politicians around the world have used this finding from R&R to justify austerity measures that have slowed growth and raised unemployment....

If facts mattered in economic policy debates, this should be the cause for a major reassessment of the deficit reduction policies being pursued in the United States and elsewhere. It should also cause reporters to be a bit slower to accept such sweeping claims at face value.

CEPR — Center for Economic and Policy Research
How Much Unemployment Was Caused by Reinhart and Rogoff's Arithmetic Mistake?
Dean Baker

Simple mistakes? No one actually checked this study until now? And they call economics a profession?