Gordon Brown, UK Chancellor, who made a career out of prudence, has proved as fallible at forecasting as his forerunners. It was only a matter of time, as forecasting itself is so flawed. Any forecast more than a year out is scarcely worth the paper it is printed on.

In the great forecasting game of who is right and wrong, two conclusions stand out. The first is that the best forecaster in any year usually only wins once, suggesting an almost random process. The second is that the forecasts that come closest are the ones extrapolated from the most recent data, an advantage that far outweighs the size of the forecasting team, the sophistication of their modelling or even the charisma of the chief economist.