The trading of open-end funds is divided into on-site trading and off-site trading. What is bought in a bank fund company is an over-the-counter transaction, and the purchase and redemption price is subject to the unit net value announced by the fund company, which is the net value announced by Tian Tian Fund Network. However, the stock market trading belongs to on-site trading, and the price fluctuates. To be exact, the price is speculative, not the real net value. Once the closing price is inconsistent with the net value announced on the same day, it is called premium, which is very common.