you don't understand. When the fund first started to sell, its net value was 1, that is, a fund was 1 yuan. Later, the fund rose to 8.5 yuan through operation, and its net value was 8.5.

if it is assumed that a fund investor bought 1, funds at the beginning of the fund sale, then the fund rose to 8.5 yuan at the price of one 1 yuan dollar, that is, 1, yuan, and the fund investor's 1, funds were worth 85, yuan, that is to say, his income was 85,-1, yuan, that is, 75, yuan.

If the fund loses money, the net value may also be .5, so the value of a fund is .5 yuan, and the investor loses 5, yuan.

I wonder if you understand my explanation.