The increase or decrease percentage of the fund refers to the increase or decrease percentage of the net value of the fund in the previous trading day, and the profit and loss of the fund can be calculated.

Suppose Xiaoxi bought a fund and spent 5,000 yuan. The net value of the fund is 2 yuan, so Xiaoxi bought a fund share of 5,000/2 = 2,500.

If the daily net value of the fund increases by 1%, the daily income of the fund is 2 * 1% * 2500 = 50 yuan, that is, each fund increases by 0.02 yuan. On the contrary, the fund 50 yuan will lose money.