profit mount Economic profits in perfect competition and monopolistic competition market has a special purpose, a positive profit can attract more enterprises to enter the market, increasing competition and push the market equilibrium price low, exclude some enterprises lack of competitiveness in the market, to achieve long-term equilibrium; On the contrary, negative economic profit can eliminate some of the original enterprises in the market, because the supply is reduced, the market equilibrium price will be pushed up, and the long-term equilibrium will be achieved. The result of the two cases is that economic profits disappear from each manufacturer and the manufacturer's total income is at the lowest point of average cost. Based on the above two kinds of comparison and analysis of the concept of earnings, reveals the inadequacy of accounting earnings, i.e., the accounting income does not take into account inflation, the production gains, goodwill to improve the impact of changes and their value, and can be found on only the pursuit of reliability, and can be measured, which affect the enterprise's profit ability and continuous operation ability. Accounting, since the 1950 s began to pay attention to absorb the income concept of some reasonable kernel of economics, the concept of modern accounting theory of income in the income concept of economics. In the 18th century, the western countries successively carried out the industrial revolution, the universal adoption of large machinery, laid the foundation for the establishment of factory system. In 1771, British man Richard arkwright1732-1792 founded the first cotton-yarn factory in the city of kron. In the 1930s and 1940s, the factory system was established in Britain, Germany and other countries. The main sex of factory system is: to carry out large-scale intensive labor; Using big machine to improve efficiency production; Implement the employment system; The division of labor is deepening and production is socialized. The establishment of factory system marks the real birth of enterprises. With the real success of the trump tax reform bill, investors in the short term focus more on whether the market has already digested this benefit. Money supply is determined by the central bank of exogenous variables, the demand for money depends on the liquidity preference of people, when people's liquidity preference to enhance tend to increase the money hold, so rates are determined by the liquidity preference in joint decision currency demand and currency supply; Loanable ZiJinLun combines the first two interest rate determinism, that interest rate is determined by the supply and demand of loanable funds, including the total savings and new bank money supply and demand including the total investment and new currency demand, interest rate decision depends on common commodity market and money market equilibrium "British shoppers more savvy than ever before, and ready to search the best deals on the net, the gimmicks and discount stores provide more and more sensible, many people now realize that may not be as they first appear.