The main reason why quantitative easing has coexisted with price stability in the US is that, since 2008, the Fed has paid interest on commercial banks' excess reserves, which previously would have been lent to businesses and households. That is why investors are right to be worried about higher inflation as demand picks up.
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CAMBRIDGE – Why has quantitative easing coexisted with price stability in the United States? Or, as I often hear, “Why has the Federal Reserve’s printing of so much money not caused higher inflation?”