A little over four years ago, as the US economy struggled to pick itself up after the dotcom crash, Alan Greenspan cut US interest rates to 1pc.
It was the first time in 50 years that the cost of borrowing had been so low, but the US Federal Reserve argued that nothing else would do. The struggling economy needed a crutch to get itself back on its feet and the Fed maintained that such a drastic step was the only way to return to growth.
It worked, but at a price that investors are only now having to pay.
With rates at 1pc, the US economy was slowly flooded with cheap money. The pattern was repeated in Europe and elsewhere as other central banks lowered lending rates.
