Does high public debt consistently stifle economic growth? A critique of Reinhart and Rogoff

We replicate Reinhart and Rogoff (2010A and 2010B) and find that selective exclusion of available data, coding errors and inappropriate weighting of summary statistics lead to serious miscalculations that inaccurately represent the relationship between public debt and GDP growth among 20 advanced economies. Over 19462009, countries with public debt/GDP ratios above 90% averaged 2.2% real annual GDP growth, not 0.1% as published. The published results for (i) median GDP growth rates for the 19462009 period and (ii) mean and median GDP growth figures over 17902009 are all distorted by similar methodological errors, although the magnitudes of the distortions are somewhat smaller than with the mean figures for 19462009. Contrary to Reinhart and Rogoffs broader contentions, both mean and median GDP growth when public debt levels exceed 90% of GDP are not dramatically different from when the public debt/GDP ratios are lower. The relationship between public debt and GDP growth varies significantly by period and country. Our overall evidence refutes RRs claim that public debt/GDP ratios above 90% consistently reduce a countrys GDP growth.