Other markets might help a bit, but even the US looks sickly, so in terms of demand we are on our own. You can see three forecasts for GDP in the final graph – from the Treasury, the Bank of England and Barclays Bank The Treasury range is by far the most optimistic. Expect it to be less optimistic when it is revised next month.If the growth forecast is revised, the whole Budget arithmetic has to be revised. The plans outlined last November already involved tax rises and already involved pushing government borrowing to 2 per cent of GDP.

There is no absolute limit on the amount that governments can borrow. Germany and France have both gone above the 3 per cent of GDP limit under the European Stability and Growth Pact this year. The US fiscal deficit seems likely to reach $400bn (£250bn), or 4 per cent of GDP, so you could say that in relative terms we are still towards the favourable end of the scale.But a billion here and a billion there and suddenly we too could be talking real money. My own guess would be that 3 per cent of GDP, or £30bn, is the practical limit on UK government borrowing.That will be the key figure to watch next month. First, we need to get the numbers for this year to see how far borrowing is going above Mr Brown’s £20bn target.

(If it doesn’t rise, look out for clever devices that shuffle spending out of this year’s accounts and into next year’s.) Second, we need to get a number for next year and, more importantly, know how the numbers might be made to fit were growth to be at the bottom end of the credible range.So we don’t just need numbers We need to have credible numbers. For his first five years as Chancellor, Gordon Brown was able to report better figures than he had initially expected The reason was that revenue was more buoyant than expected. Now the very forces that made things turn out better than expected have gone into reverse and are making them seem worse. The fact that other governments are in a similar situation is small comfort for British taxpayers, who are the people who ultimately have to cope with the consequences.And that, next month, will be the crucial element in the mix. How will we react to higher taxation? Will we go on trying to maintain our spending? If we do, then the economy carries on growing and the Budget sums remain manageable.

But this comes at the cost of greater household debt that at some stage will have to be repaid. Or will we become frightened and cut back? In that case, the Government’s debt becomes larger – but our own family finances improve.So the issue next month may be partly one of “which way will Gordon jump?” But is it also “which way will we jump?” too.. Broken men are two a penny in the City now. We seem to have created a system in the last 10 years that requires regular blood sacrifices in the Temple of Mammon

Broken men are two a penny in the City now. But a decade ago it was a rare thing, and the public humiliation of an analyst sticks in my mind. He had staked his career and reputation on a reported pledge from the board of BP not to cut the dividend.