Valuation bubble Data released by the American petroleum institute (API) showed that U.S. crude oil inventories fell 5.2 million barrels in the week ended Dec. 15, down from an expected 35.18 million barrels. Refinery inventories fell more than expected, while gasoline inventories rose, but were less than expected. The overall API data is good and good for oil prices. Investors are confused and lost on the way forward, the confusion and bewilderment itself will keeps everyone to learn, so investors are eager to learn has been exist, is the power of the instinct of the profit will lead us to learn. It is not easy to learn the key question is: futures, its difficulty may not be less than the difficulty of the transaction, this kind of difficult to make a lot of people were forced to study only a period of time, that then is in a state of flow for a long time, but it is difficult to further more in-depth study. Some western economists believe that enterprises as an organizational form of production are, in part, an alternative to the market. After the black Friday rush, consumer spending is being squeezed.