Oil prices skid on China currency move

US oil prices sank to their lowest level in more than six years Tuesday after a surprise currency devaluation in China raised worries about the world's second-biggest economy. US benchmark West Texas Intermediate for delivery in September fell $1.88 to $43.08 a barrel on the New York Mercantile Exchange, the lowest level since March 2009. China's central bank devalued its yuan currency Tuesday by nearly two percent against the US dollar, as authorities said they were seeking to push ma