Your question is not used to calculate the income of fixed investment, but to calculate the final value of money. As far as the topic is concerned, you still lack a condition-you don't know whether the annual income of 10% is nominal or actual, which will lead to the uncertainty of the real interest rate and the uncertainty of the final numerical calculation results. As for calculating the income of fixed investment, it is actually a very simple matter. Fixed investment only averages your purchase cost. If you want to know how much money you earned after a certain period of time, you just need to look at the total fund share in your fixed investment account (this is the sum of the fund shares you bought after each fixed investment, or you can calculate it yourself). Multiply this total fund share by the current net fund value, which is your current total assets. Your income is equal to the total assets MINUS the capital invested since the fixed investment, which is your net income. If you want to calculate the net investment return rate, that is, the net investment return rate after deducting the handling fee, then you need to multiply the fund shares bought after each fixed investment by the net fund value at that time, and then add these values several times, which is your pure investment fund (this way of calculating the investment amount by actually buying the fund shares has excluded the handling fee). Subtracting this pure investment fund from your total assets is your pure return on investment. It will be complicated to express it in words. You can make an EXCEL table with columns set as date, fixed investment amount, net fund value, subscription share and total fund value (that is, pure investment mentioned above). When you have certain data, you can use various EXCEL functions such as summation to automatically calculate your investment income. If you want an example, you can use this method to find an existing fund in the market and practice it yourself with its data in the past two years.