After hitting a five-year high in 2015, the global growth in demand for oil is expected to fall by about a third next year, adding further strain to an already oversupplied crude market.

A 40% decline in the price of oil since last year has boosted demand, encouraging motorists, consumers and companies to top up. But the economic slowdown in China and elsewhere in Asia could sap that demand, according to analysts and big energy watchdogs.

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