An employee walks on top of an oil tank at a Sinopec refinery in Wuhan, Hubei province, in this April 25, 2012 file photo. China's rising fuel demand saw it overtake the United States as the world's ... more 
An employee walks on top of an oil tank at a Sinopec refinery in Wuhan, Hubei province, in this April 25, 2012 file photo. China's rising fuel demand saw it overtake the United States as the world's top net oil importer last month. As China's importance for global oil markets grows, traders looking for an edge are hunting for smarter ways to assess demand and supply in a country that publishes relatively little energy sector data. To match CHINA-USA/OIL REUTERS/Stringer/Files (CHINA - Tags: ENERGY BUSINESS) CHINA OUT. NO COMMERCIAL OR EDITORIAL SALES IN CHINA less 
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Reuters | Photo By DARLEY SHEN / REUTERS
Thu, Oct 31, 2013 5:33 PM EDT