The comment that God created economists in order to make astrologers look credible would be moderately amusing if it was not so near the mark. In the last few years, most practitioners of ‘the dismal science’ failed to anticipate the consequences of the borrowing-led boom up to 2008. To compound these mistakes, they are now struggling to explain where we are and where we are going in the next year or two.

In HM Treasury’s latest monthly summary of independent forecasts, for example, the range of estimates for UK growth in 2012 is from a low of -1.3% to a high of +1.5%, hardly helpful for businesses trying to plan.

Part of the confusion may be to do with definitions and the language of economics. But a bigger part may be because the current situation is unprecedented and, without past reference points to guide them, the models on which so many forecasters depend are of little use.