Although an enterprise's internal trade fair eliminates or reduces some of the market transaction costs, it also brings with it the specific transaction costs of the enterprise. The main reason for this defect is also the incompleteness of information. Specifically, first, there are various contractual relationships among enterprises, including contractual relationship between enterprises and workers, contractual relationship between enterprises and managers, etc. The enterprise should supervise the work of the workers and products that it employs, as well as the managers and other personnel, and induces them to work hard for the enterprise. So, companies are signing contracts and spending on oversight and incentives. Secondly, on the one hand, corporate decision makers often need to obtain information from subordinates. On the other hand, the decision-making information of the upper level of the enterprise should be realized by passing it to the subordinate. The information transmission of these two different directions will be distorted by the increase of subordination of enterprise scale, resulting in the loss of enterprise efficiency. Once again, the subordinate of the enterprise often conceals or passes the wrong information to the superior for selfish motives, so that the superior can make decisions that benefit the subordinate. Or, the subordinate's decision to the superior only passes or executes the part that is advantageous to oneself. These will result in the loss of enterprise efficiency. Thus, the expansion of enterprises is limited. According to coase's theory, the scale of the enterprise should be expanded to this point, that is at this point to increase the cost of an internal exchange cost equals the cost through the market exchange cost and so on. Modern economy, the interest rate as the price of money, not only restricted by many factors in the economic and social, and changes in interest rates to have a great impact on the economy as a whole, as a result, modern economists are studying the interest rate decision problem, pay special attention to the relationship between the variables and the balance of the economy as a whole, the interest rate decision theory has experienced the classical interest rate theory, Keynes's interest theory, interest rate in loanable funds theory and is-lm analysis as well as the contemporary evolution of dynamic interest rate model, the development process. "People say 'oh, those experts', but we're seeing what we call potential risks being rolled out. This is not what the experts say, this is what the economy is showing. " The basic economic unit of society in the primitive society of the clan, tribe, slave owners in the slave society, feudal society's family and the manual workshop, after the evolution of the form of this modern form in a capitalist society was born enterprise. Gas car