In the week ended Dec. 15, U.S. crude stocks fell 520 barrels to 438.7 million barrels, the API said, with analysts predicting a decrease of 3518,000 barrels. Cushing's crude inventories rose by 70,000 barrels. Mooney and si prowse in its around the main accounting principles for enterprises ", not only emphasize to determine profits in a timely manner, and emphasizes the necessary through division operating earnings, the gains and the impact of price changes, to improve the comparability of financial statements and understandability. The value contains human consciousness and the double development of life, including the unity of human and external nature. All the development of the self - world is of value. The core essence of value is the free man, and the man who creates himself is the free man. Man is the ultimate object of value, man is the value ontology, man's behavior is the source of value, and the development of man is the result of value. The development of human beings is the unity of human's inner contradictions and external contradictions. It is the overall development of human consciousness and human life and the whole development of human and nature. That is, the self-creation of man and the unity of external creation and creation of nature, and the creation of this freedom is also the value behavior, so the whole value is the realization of freedom The response to single factor value is trend. The tendency is the selection bias produced by the stimulation of the organism on a single environmental factor, which is the directional response form of the organism to the external stimulus, including the two basic forms of orientation and avoidance. The tropism has the tendency of phototropism, thermal tendency, wetness, tendency, and oxygenicity. It has the avoidance of light, heat, moisture, anaerobic and so on. For example, the acidity of paramecium, the thermal tendency of bedbugs and the phototropism of insects. The trend is the common response of low biological cells, biological tissues and protozoa. Tropism is in a series of internal inductance organically combined in a certain direction, to form a structure of ordering, and external single environment factor to form a single reaction, the biological function between the body and the external environment on the coherent function, to accelerate the ordering of the body development. When this series of inductivity is combined in a positive way, the tendency is formed. When this series of induction is combined in reverse, it forms a negative trend - the avoidance. In summary, the trend is the most elementary preordinate response to the external things of single factor value.