By the numbers: Fragile states turn to high rates for rescue

As the global economy slows, central bankers in much of the developed world slashed interest rates to try to spur growth.

But if your economy is in serious trouble, the economic pain of higher rates may be your only option to prevent a deeper collapse.

Russia became the latest such case on Monday, with its central bank jacking rates higher in an effort to prevent widespread economic chaos. Plunging oil prices have clobbered the Russian ruble and sent investors scurrying out of the country. Higher rates may help slow the exodus and support the ruble, but the sharp rise in borrowing costs is a major headwind for local businesses and Russian consumers.

To demonstrate the link between high rates and shaky economies, compared the list of the world's most troubled states — as measured by the Fund for Peace's Fragile States Index — with the current interest rate in the roughly 90 central banks tracked by Central Bank News.

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The correlation is pretty clear: the higher a country's fragile state index, the more likely it is to have higher official interest rates.

Those rates, of course, don't necessarily reflect the true cost of borrowing. Many fragile countries also have relatively weak financial systems and robust black market economies, where central bank rates don't apply.

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