Some economists argue that recessions result in a permanent loss of output.

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That means the permanent loss to output, from the crisis is that much higher, and the scope for what we would call a decent recovery is even smaller than we thought.

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As the unemployment rate has declined, it has actually worried economists that are seeing signs of a permanent reduction in the potential output of the U.S. economy.

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B2B e-commerce will cause a permanent increase in the level of output by an average of 5% in the rich economies, with over half of this increase coming through within ten years.

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It says Germany will suffer a "permanent scar" on its level of output, with its GDP reduced by between 0.1 and 0.5%.

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If he's wrong - if there is, in fact, a faster growth path available, which would not undermine market confidence, then the government's strategy could be making the supply side problem a self-fulfilling prophesy, by condemning us to unnecessarily slow growth which could have permanent effects on Britain's potential output.

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This rests on the notion that there is a fixed ceiling for output, rising over time, so any shortfall against potential is a permanent loss.

ECONOMIST: Should we learn to love recessions?