Ever since the crash in 2008, the central banks in the advanced economies have had but one obsession — how to set monetary policy to ensure the maximum growth rate in aggregate demand. Interest rates at the zero lower bound, followed by a massive increase in their balance sheets, was the answer they conjured up.
Now, those central banks contemplating an exit from these policies, primarily the US Federal Reserve and the Bank of England, are turning their attention to the supply side of their economies. When, they are asking, will output reach the ceiling imposed by the supply potential of the economy?
The Bank of England has been in the lead here, with the Monetary Policy Committee recently conducting a special study of the supply side in the UK. Its conclusion was that gross domestic product is now only 0.5 per cent below potential, which implies that tighter monetary policy will soon be needed if GDP growth remains above potential for much longer.
In the US, the Fed has been much less specific than that, but the unemployment rate has now fallen very close to its estimate of the natural rate (5.0-5.2 per cent). Sven Jari Stehn of Goldman Sachs has used the Fed staffers’ supply side models to calculate that their implied estimate of the US output gap may be only 0.6 per cent, not far from the UK figure.
If the UK and US central banks were to act on these calculations, the implication would be that they no longer hold out much hope that they can ever regain the loss in potential output that has occurred in the past decade, relative to previous trends. That would be a massive admission, with an enormous implied sacrifice in future output levels if they are wrong. It would also be very worrying for financial assets, since it would draw the market’s attention to a downgrade in the Fed’s estimation of the long-run path for GDP. Read more