1. Simple calculation method of income: use some fund shares * net value, and then compare it with the money you invested. If it is a cash dividend, you should also count the money you have already spent.

2. In the final analysis, the income of the fund is related to the investment ability of the fund company. As long as the gap between the investment ability of the fund company and the average rate of return of the whole market (all similar funds) is not too big, it means that the fund is not too bad.

Investment funds are not bank savings and can never be measured by the concept of interest. Investment funds are risky and may suffer loss of principal. The reason why we don't have to care about the short-term ups and downs of the market is because the purpose of fixed investment is to obtain the long-term average rate of return of the whole market with small, sustained and stable investment. The longer the time, the less risk. This also requires a premise that investment funds will not go bankrupt, otherwise they will suffer huge losses.