No matter how it goes up or down, the shareholding share remains unchanged. If the fund falls and rises back to its original position, the net value will remain unchanged. If you hold it for a short time, you won't lose money if you don't sell it. If you sell it immediately, you will definitely lose money.

This is a loss.

This is the open plan of the fund. You can calculate it yourself. The first day you bought 10000, the next day it went up 1%, and the third day it went down 1%. The net value is the same as the first day, but obviously you lost 1 yuan. Similarly, if you fall first and then rise, you still lose a dollar. The more ups and downs in the middle, the more losses under the same amplitude. So try to find a smaller retreat. Because when you rise high, when you retreat, you will fall even worse.

You have 10000 yuan now. If the net value of the fund unit you buy is 1 yuan, then you will hold 10000 shares after you buy it.

On the first day, the unit net value fell to 0.9 yuan, which means that you only have 0.9 yuan x 10000=9000 yuan, and you lost 1000 yuan, but you still hold 10000 copies, but the unit price of each copy has dropped.

The next day, the unit net value rose to 1 yuan, which means you have 1 yuan X 1 ten thousand yuan = 1 ten thousand yuan, which means you still have 1 ten thousand yuan.

In the end, you have no profit or loss.