Escreve Robert Shiller acerca da célebre associação que Rogoff e Reinhardt fizeram sobre taxas de endividamento acima de 90% e redução do crescimento:
"A paper written last year by Carmen Reinhart and Kenneth Rogoff, called “Growth in a Time of Debt,” has been widely quoted for its analysis of 44 countries over 200 years, which found that when government debt exceeds 90% of GDP, countries suffer slower growth, losing about one percentage point on the annual rate.Gostei também muito deste bocadinho:
"One might be misled into thinking that, because 90% sounds awfully close to 100%, awful things start happening to countries that get into such a mess. But if one reads their paper carefully, it is clear that Reinhart and Rogoff picked the 90% figure almost arbitrarily. They chose, without explanation, to divide debt-to-GDP ratios into the following categories: under 30%, 30-60%, 60-90%, and over 90%. And it turns out that growth rates decline in all of these categories as the debt-to-GDP ratio increases, only somewhat more in the last category.
"There is also the issue of reverse causality. Debt-to-GDP ratios tend to increase for countries that are in economic trouble. If this is part of the reason that higher debt-to-GDP ratios correspond to lower economic growth, there is less reason to think that countries should avoid a higher ratio, as Keynesian theory implies that fiscal austerity would undermine, rather than boost, economic performance.
"The fundamental problem that much of the world faces today is that investors are overreacting to debt-to-GDP ratios, fearful of some magic threshold, and demanding fiscal-austerity programs too soon. They are asking governments to cut expenditure while their economies are still vulnerable. Households are running scared, so they cut expenditures as well, and businesses are being dissuaded from borrowing to finance capital expenditures.
"The lesson is simple: We should worry less about debt ratios and thresholds, and more about our inability to see these indicators for the artificial – and often irrelevant – constructs that they are."
"If economists did not habitually annualize quarterly GDP data and multiply quarterly GDP by four, Greece’s debt-to-GDP ratio would be four times higher than it is now. And if they habitually decadalized GDP, multiplying the quarterly GDP numbers by 40 instead of four, Greece’s debt burden would be 15%. From the standpoint of Greece’s ability to pay, such units would be more relevant, since it doesn’t have to pay off its debts fully in one year (unless the crisis makes it impossible to refinance current debt).".