Frank Zappa once said that rock journalism is people who can’t write, interviewing people who can’t talk, for people who can’t read. Something similar can be said for stock markets. They are mostly myopic, unpredictable, crazily mispriced and followed by equally clueless investors. On the other hand, just like music itself, equities can sometimes point to something bigger.

Now may be such a time. In the past fortnight or so a slew of US economic data has been on the weaker side. On Wednesday, a manufacturing survey from the Federal Reserve Bank of New York revealed that a quarter of respondents thought that conditions had worsened in May, compared with just 11 per cent the month before. A small business survey on Monday was also softer. This follows a terrible monthly payrolls report and data showing that house prices have now officially double dipped.

But whereas before equity markets took soggy numbers as a positive sign that policy interest rates would stay low, Wednesday’s more than