Spring has arrived and policymakers see “green shoots”. Barack Obama's economic adviser, Lawrence Summers, says the “sense of freefall” in the US economy should end in a few months. The president himself spies “glimmers of hope”. Ben Bernanke, chairman of the Federal Reserve, said last week “recently we have seen tentative signs that the sharp decline in economic activity may be slowing, for example, in data on home sales, homebuilding and consumer spending, including sales of new motor vehicles”.

Is the worst behind us? In a word, No. The rate of economic decline is decelerating. But it is too soon even to be sure of a turnround, let alone of a return to rapid growth. Yet more remote is elimination of excess capacity. Most remote of all is an end to deleveraging. Complacency is perilous. These are still early days.

As the Organisation for Economic Co-operation and Development noted in its recent Interim Economic Outlook, “the world economy is in the midst of its deepest and most synchronised recession in our lifetimes, caused by a global financial crisis and deepened by a collapse in world trade”. In the OECD area as a whole, output is forecast to contract by 4.3 per cent this year and 0.1 per cent in 2010, with unemployment rising to 9.9 per cent of the labour force next year. By the end of 2010, the “output gap” – a measure of excess capacity – is forecast to be 8 per cent, twice as large as in the recession of the early 1980s.