Interest rate, in the form of expression, refers to the ratio of the amount of interest to the total amount of borrowed capital in a certain period of time. [1] the interest rate is the interest level per unit time of the unit currency, indicating the interest rate. Economists have been looking for a theory that can fully explain the structure and change of interest rates. Interest rates are usually controlled by the central bank of the country and administered by the federal reserve board in the United States. Today, interest rates are one of the important tools for macroeconomic regulation. 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. Securities companies that need to invest in securities should apply for the corresponding investment financial accounts. Account can be used in financial investment in stocks (including A shares, B shares and H shares, etc.), bonds (including Treasury bonds, corporate bonds, corporate bonds, etc.), futures (including financial futures, such as stock index futures, foreign exchange futures, commodities such as metal futures, futures of agricultural products, etc.) and so on A series of financial instruments to invest in securities. The opening of the securities account can be handled by the business department of the securities companies and it needs to be handled within the trading day. Some securities companies such as guotai junan securities through the provinces website (e.g., guotai junan guangdong) online booking, through the appointment of account opening time is more flexible and corresponding work time, lunch time, daily can open an account on Saturday. Mun Chun Loh, director of private wealth at GoldSilver Central, said gold has rebounded from a cyclical low and will tend to be lighter as the long holiday begins.