Why the oil price slump hasn't kickstarted the global economy

There has only been a modest boost to global growth despite the oil price plummeting to as low as $35 a barrel. But as prices fall so the risks to producers rise

One of the biggest economic surprises of 2015 is that the stunning drop in global oil prices did not deliver a bigger boost to global growth. Despite the collapse in prices, from over $115 a barrel in June 2014 to $45 at the end of November 2015, most macroeconomic models suggest that the impact on global growth has been less than expected - perhaps 0.5% of global GDP.

The good news is that this welcome but modest effect on growth probably will not die out in 2016. The bad news is that low prices will place even greater strains on the main oil-exporting countries.

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