It never had any validity anyway; it was another phony intellectual "cover" for the unbridled greed of the economic elites, nothing more and nothing less.
Reinhart-Rogoff lasted longer, even though serious questions about their work were raised early on. As early as July 2010 Josh Bivens and John Irons of the Economic Policy Institute had identified both a clear mistake—a misinterpretation of US data immediately after World War II—and a severe conceptual problem. Reinhart and Rogoff, as they pointed out, offered no evidence that the correlation ran from high debt to low growth rather than the other way around, and other evidence suggested that the latter was more likely. But such criticisms had little impact; for austerians, one might say, Reinhart-Rogoff was a story too good to check.
So the revelations in April 2013 of the errors of Reinhart and Rogoff came as a shock. Despite their paper’s influence, Reinhart and Rogoff had not made their data widely available—and researchers working with seemingly comparable data hadn’t been able to reproduce their results. Finally, they made their spreadsheet available to Thomas Herndon, a graduate student at the University of Massachusetts, Amherst—and he found it very odd indeed. There was one actual coding error, although that made only a small contribution to their conclusions. More important, their data set failed to include the experience of several Allied nations—Canada, New Zealand, and Australia—that emerged from World War II with high debt but nonetheless posted solid growth. And they had used an odd weighting scheme in which each “episode” of high debt counted the same, whether it occurred during one year of bad growth or seventeen years of good growth.
Without these errors and oddities, there was still a negative correlation between debt and growth—but this could be, and probably was, mostly a matter of low growth leading to high debt, not the other way around. And the “threshold” at 90 percent vanished, undermining the scare stories being used to sell austerity.
The austerity crowd is trying to cover it all up, but to them it is more about ideology than fact anyway.
Too bad Obama still believes in that nonsense.