First of all, you need to understand the trading characteristics of the fund. Fund subscription, subscription and redemption by share. Now give a simple example. For a fund, the subscription rate and redemption rate are both 1% (just for example, there is generally no such high rate).

You need to apply for the amount if you buy it. Suppose you buy 1 ten thousand yuan. After deducting 1% service charge, it is 100 yuan, and there is still 9900 yuan.

Suppose it is a newly issued fund, that is, 1 yuan per share, then you subscribed for 9900 shares. A month later, the fund rose to 1. 1 yuan per share. Then the reference market value is 9900 X 1. 1 yuan/share = 10890. Sell 9900 copies if you want to sell them. That is10890-10890x1%=10781.1yuan. It is equal to earning 78 1. 1 yuan.