Will they or won't they? On both sides of the Pacific, debate over the Chinese currency is burning. Will the Chinese government allow the renminbi to appreciate against the dollar once more and, if so, will they make a one-off revaluation or allow a creeping, managed appreciation along the lines seen between 2005 and 2008?

Judged in economic terms, the question seems straightforward, if finely poised. Chinese producer price inflation is rising sharply, in part as a result of the higher import prices that an unnecessarily weak currency entails. Consumer price inflation is also rising, thanks to higher food prices, and so a stronger currency might be a good way to stop overheating.

It would make a sensible addition to the other measures that China has taken to try to cool the effects of the drastic stimulus it started in late 2008.