The Financial Post reports in its Thursday, Aug. 15, edition that oil tumbled the most in a week as global financial markets swooned and swelling U.S. crude stockpiles reinforced fears about an economic slowdown. A Bloomberg dispatch to the Post reports that futures closed down 3.3 per cent in New York on Wednesday, joining a slide in equities that saw 98 per cent of the stocks in the S&P 500 Index drop. American crude inventories posted a surprise increase for the second straight week, U.S. data showed. That accelerated a flight from commodities and higher-risk assets as sagging Treasury yields sounded alarm bells. "People are panicking," Mark Waggoner, president of Oregon brokerage Excel Futures, said, adding they are concerned the economy is slowing. West Texas Intermediate crude for September settled $1.87 (U.S.) lower at $55.23 (U.S.) a barrel on the New York Mercantile Exchange. Brent for October settlement decreased 3 per cent to $59.48 (U.S.) on the ICE Futures Europe Exchange.