Is the market turbulence of the last week telling us something or is it no more than “a tale told by an idiot, full of sound and fury, signifying nothing”? Some analysts are prepared not only to explain day-to-day movements in markets, but to predict them. I am neither clever enough for the former, nor rash enough for the latter. I am prepared, however, to make four statements: first, a period of market volatility is welcome; second, core equity markets do look overvalued; third, that this does not appear to be the case is due to the extraordinary condition of the world economy; finally, the big question is how long those conditions will endure.
Any long period of market stability encourages speculation. Taken to excess, such risk-taking, particularly when fuelled by huge amounts of borrowing, can create significant instability. At a time when asset markets are generally buoyant and risk premiums low, the need for a reminder of riskiness is valuable. It is far better, as natives of San Francisco must know, to suffer a series of mini-earthquakes than a long period of calm, followed by a huge one. Similarly, euphoria in markets is dangerous. From time to time it needs to be punctured, before bubbles reach the proportions seen in Japanese markets in 1990 and US markets in 2000.
The remainder of Martin Wolf’s column can be read here (FT.com subscribers only). Discussion from our guest economists is free.