Monetary funds can be divided into Class A and Class B according to the size limit of participating funds. Class A is for small and medium investors, and Class B is for institutions and large investors. The minimum subscription limit of Class A monetary funds is generally 1 0,000, and the annual rate is 0.68%; 5 million copies of Class B, with an annual interest rate of 0.44%. That is to say, the income of Class B monetary fund under the same fund company is about 0.24% higher than that of Class A. According to the income carry-over, it can be divided into two types: daily carry-over and monthly carry-over. The former is credited to the investor's principal every day to participate in the next day's income distribution, while the latter only carries forward the income share once a month. If the two money funds publish the same income every day, the actual income of the money fund converted by daily settlement is slightly higher than that of the money fund converted by monthly settlement. In fact, for small and medium investors, the gap between them is limited. Money market funds also have risks, but compared with their low returns (about 2%), the risks are relatively small.