government grants non profit organizations The American petroleum institute (API) released data showing a decline in U.S. crude oil and refined refining inventories, while gasoline inventories rose. The investment of securities provides an important means for the central bank to conduct financial macro-control, which is of great significance to the sustainable and efficient development of the national economy. When the economy overheats and inflation rises, interest rates are raised and credit tightened. When the overheated economy and inflation are under control, the interest rate is duly lowered. Interest rates are therefore one of the fundamental economic factors. Interest rates are an important financial variable in economics, and almost all financial phenomena and financial assets have more or less connection with interest rates. During the depression, the rate of interest reduction, the expansion of money supply, stimulate economic development. During the expansion period, the interest rate increases, the money supply is reduced, and the economic development is suppressed. So, interest rates have a big impact on our lives.