The investment income of bonds mainly consists of two parts: one is the fixed interest income from bonds, and the other is the price difference earned in market transactions. Of these two parts of income, interest income is fixed, and the bid-ask spread is greatly affected by the market. The factors that affect the bond investment income are: (1) The higher the coupon rate of coupon rate bonds, the higher the bond interest income and the higher the bond income. The coupon rate of bonds depends on the market interest rate at the time of issuance, the maturity of bonds, the credit level of issuers, the liquidity level of bonds and other factors. The higher the market interest rate at the time of issuance, the higher the coupon rate; The longer the bond term, the higher the coupon rate; The higher the issuer's credit rating, the lower the coupon rate; The higher the liquidity of bonds, the lower the coupon rate. (2) Market interest rate and bond price According to the calculation formula of bond yield, the change of market interest rate is inversely proportional to the change of bond price, that is, when the market interest rate rises, the bond price falls, while when the market interest rate falls, the bond price rises. The change of market interest rate causes the change of bond price, which brings price difference to bond trading. When the market interest rate rises, the bid-ask spread of bonds is positive, and the investment income of bonds increases; When the market interest rate decreases, the bid-ask spread of bonds is negative, and the investment income of bonds decreases. With the rise and fall of market interest rate, if investors can buy and sell bonds in time, they can get greater bond investment income. Of course, if investors buy and sell bonds at the wrong time, it will also reduce the investment income of bonds. Associated with the face value of bonds and coupon rate, when the bond price is higher than its face value, the bond yield is lower than that of coupon rate. On the contrary, it is higher than coupon rate. (3) Investment cost of bonds The cost of bond investment is roughly divided into three parts: purchase cost, transaction cost and tax cost. The purchase cost is the amount paid by investors to buy bonds (the product of the number of bonds purchased and the price of bonds, that is, the principal); Transaction costs include brokerage commission, transaction fee and transfer fees. At present, the interest income of national debt is tax-free, but the interest income of corporate bonds still needs to be taxed, and institutional investors also need to pay business tax. Taxation is also an important factor affecting the actual investment income of bonds. The higher the bond investment cost, the lower the investment income. Therefore, the bond investment cost is a factor that investors must consider when comparing and selecting bonds, and it must also be deducted when calculating the actual yield of bonds. (4) Market supply and demand, monetary policy and fiscal policy, market supply and demand, monetary policy and fiscal policy will all have an impact on bond prices, thus affecting the cost for investors to buy bonds. Therefore, market supply and demand, monetary policy and fiscal policy are also factors that cannot be ignored when we consider investment income. Although the investment income of bonds is influenced by many factors, bonds are essentially a fixed income tool, and their price changes will not fluctuate as much as stocks, so the income is relatively fixed and the investment risk is small, which is suitable for investors who want to obtain fixed income. Securities Law Article 2 This Law shall apply to the issuance and trading of stocks, corporate bonds and other securities legally recognized by the State Council within the territory of People's Republic of China (PRC); Matters not covered by this Law shall be governed by the Company Law of People's Republic of China (PRC) and other laws and administrative regulations. This Law shall apply to the listing and trading of government bonds and securities investment fund shares; Where other laws and administrative regulations provide otherwise, such provisions shall prevail. Measures for the administration of the issuance and trading of securities derivatives shall be formulated by the State Council in accordance with the principles of this Law.