Professor Tim Congdon from International Monetary Research said US bank loans have fallen at an annual pace of almost 14pc in the three months to August (from $7,147bn to $6,886bn).

"There has been nothing like this in the USA since the 1930s," he said. "The rapid destruction of money balances is madness."

The M3 "broad" money supply, watched as an early warning signal for the economy a year or so later, has been falling at a 5pc annual rate.

Similar concerns have been raised by David Rosenberg, chief strategist at Gluskin Sheff, who said that over the four weeks up to August 24, bank credit shrank at an "epic" 9pc annual pace, the M2 money supply shrank at 12.2pc and M1 shrank at 6.5pc.

"For the first time in the post-WW2 [Second World War] era, we have deflation in credit, wages and rents and, from our lens, this is a toxic brew," he said.

It is unclear why the US Federal Reserve has allowed this to occur.

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