Well, if the set interest rates lower than the natural rate then they will have rising inflation and output which will mean an ever increasing natural rate and even faster inflation until eventually the economy moves into hyper-inflation and their control over the medium of exchange collapses.

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The Germans abhor inflation thanks to their historical run-in with hyper-inflation from 1921 to 1924, a catastrophe so severe that by its finish, the Weimar Republic was forced to issue one trillion mark notes.

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This Pavlovian fear is even stronger in Germany, where the hyper-inflation of the 1920s is linked in policymakers' minds to the rise of Hitler.

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But Mr Duhalde's fate, and Argentina's, is likely to be determined by the government's success or failure in freeing the currency without triggering hyper-inflation.

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John Robertson, an economist in Harare, says the country's hyper-inflation is being driven primarily by the government borrowing money to cover recurring costs such as wages and operating expenses.

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The 1980 map of Latin America was largely one of authoritarian, often military governments, generally controlled by small oligarchies, with hyper-cyclical, commodity-based economies, nearly all plagued by huge debt and hyper-inflation.

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The collapse of the Austro-Hungarian Empire saw the rebirth of Austria in 1918 as a rather diminished republic, while the rampant hyper-inflation of 1923 finished off the old imperial currency, the krone.

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