Oliver Blanchard
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IMF warns of economic 'rollercoaster'

17 April 2012 Last updated at 16:26 BST

The International Monetary Fund (IMF) has said that "some optimism has returned" to the global economy and has predicted slightly faster growth.

The IMF revised world economic growth for 2012 to 3.5%, up from its previous forecast of 3.3%.

However, Oliver Blanchard, the Chief Economist at the IMF identified the eurozone crisis as the greatest threat to economic growth.