Brent crude prices fell by 44 cents in a day and decreased to as low as $51.50 per barrel, the lowest price since February 2.Record July production levels announced by the Organization of the Petroleum Exporting Countries (OPEC) and weak economic data from the world's second largest oil consumer China were the main driving factors in the decrease in Brent prices.U.S. crude prices also fell to $46.35 per barrel, the lowest in four months.