Inflation is always and everywhere a monetary phenomenon.” Milton Friedman made this remark in 1963. At that time, few macroeconomists agreed with him. Twenty years later a high proportion did. Twenty years after that, again most did not. Today, almost another two decades later, economists have to take money seriously again. If money is ignored, it will take revenge. As Bridgewater’s Ray Dalio recently asked: “Where is the understanding of history and the common sense about the quantity of money and credit and the amount of inflation?”
The idea that there is a link between the money supply and inflation is very old. When people are holding more money than they desire, they will want to get rid of it. With any other asset, this would lower its price. But the nominal price of money is fixed: a dollar is a dollar. The adjustment comes via higher prices for everything else — or inflation.
After an exceptional monetary expansion in 2020, we are surely seeing this. I noted the possibility in May that year. Tim Congdon, a well-known monetarist, had argued this before me. According to the Center for Financial Stability, “Divisia M4” (an index that weights the components by their role in transactions) grew by 30 per cent in the year to July 2020, almost three times as fast as in any similar period since 1967. No such thing happened after the 2008 financial crisis. Many then worried over the expansion of the monetary base. But that did not matter because it did not affect broader aggregates. (See charts.)