Money managers reduced their combined net-long positions by 3.9% in 18 US raw materials futures and options to a total of 798,787 contracts last week on concern that Europe’s continued debt crisis will slow demand, Bloomberg reported. Fifteen of the 24 commodities tracked by the Standard & Poor’s GSCI index fell last week, while the index as a whole has lost 14% since reaching a 32-month high in April. “When you look out and see what’s happening in Europe, you get very worried that demand could disappoint,” said Nic Johnson, an asset manager at Pacific Investment Management. Analysts predict that the US gross domestic product will grew 2.05% in 2012, while China’s economy is expected to grow 8.6%. China is the largest consumer of many global commodities including copper and corn. “People are waiting on the sidelines,” asset manager Christoph Eibl said. “People will go back into commodities because they understand that there is a scarcity and that we’re not hitting a recession or a depression. It may be a little bit of a slowdown, but it’s not a recession.”