The risks of disinflation and deflation

From an article in The Economist:

WHAT is a central banker’s main job? Ask the man on the street and the chances are he will say something like “keeping a lid on inflation”. In popular perception, and in their own minds, central bankers are the technicians who squeezed high inflation out of the rich world’s economies in the 1980s; whose credibility is based on keeping it down; and who must therefore always be on guard lest prices start to soar. Yet this view is dangerously outdated. The biggest problem facing the rich world’s central banks today is that inflation is too low...

The most obvious danger of too-low inflation is the risk of slipping into outright deflation, when prices persistently fall. As Japan’s experience shows, deflation is both deeply damaging and hard to escape in weak economies with high debts. Since loans are fixed in nominal terms, falling wages and prices increase the burden of paying them. And once people expect prices to keep falling, they put off buying things, weakening the economy further. There is a real danger that this may happen in southern Europe...

What’s more, too little inflation will undermine central bankers’ ability to combat another recession. Normally, during a period of growth bankers would raise rates. But policy rates are close to zero, and central bankers are reliant on “unconventional” measures to loosen monetary conditions, particularly “quantitative easing” (printing money to buy bonds) and “forward guidance” (promising to keep rates low for longer in a bid to prop up people’s expectations of future inflation). Should the economy slip back into recession, the central bankers will find themselves unusually impotent...

More at the link, and in this companion article.