Global crude oil prices fell more than 4 percent, to fresh 6-1/2-year lows, today, after Chinese stock markets suffered their biggest one-day drop since the global financial crisis, intensifying worries over the outlook for global oil demand.Brent crude oil futures dropped to 43.28 dollars a barrel–its weakest since March 2009. U.S. light crude fell as low as 38.69 dollars a barrel. U.S. crude is now down more than 17 percent this month, while Brent is down more than 10 percent.