Speculative trading. The prices of steel, oil and oil are directly proportional to the non-commercial positions for market speculation. The speculative trading of speculative funds in 2008 and 20 15 is an important reason for the sharp rise and fluctuation of international oil prices. Petroleum refers to the mixture of natural gaseous, liquid and solid hydrocarbons. Petroleum is divided into crude oil, natural gas, natural gas liquid and natural tar.