There are probably several reasons. First, there are a large number of shares to be lifted, accounting for too large a proportion. Second, too many retail investors are optimistic about Fii, and they have been optimistic about Fii for a long time and persistently hold and continue to lose. Sell ??high and buy low every day, or keep covering positions to spread low costs. The third is the important index stocks of the Shanghai Composite Index. They are large in the market and have high weight. They are used as targets for market control by major institutions. Recently, they are used as tools to smash the index. Major institutions can make money by doing both short and long positions, which affects the stock index futures index.

1. Stock (stock) is a kind of marketable security. It is a certificate issued by a joint-stock company to prove the shares held by shareholders. Shareholders are the owners of the company and have limited liability to the company to the extent of their capital contribution, bear risks and share profits.

2. Stocks have the following four properties: First, stocks are securities, which reflect the rights of the stock holders to the company; second, stocks are warrant securities. Stocks represent the rights of shareholders. When the company's stocks are transferred, the rights and interests of the company's shareholders will also be transferred with it; third, stocks are essential securities, and the recorded contents and matters must comply with the provisions of the law; fourth, stocks are tradable securities. securities. Stocks can be traded on the securities exchange market in accordance with the law.

3. Trading hours The trading hours of most stocks are: Trading hours are 4 hours, divided into two periods: Monday to Friday 9:30 to 11:30 am and 13:00 to 15 pm :00. Starting at 9:15 a.m., investors can place orders, and the order price is limited to plus or minus 10% of the closing price of the previous business day, that is, between the daily price limit and the daily price limit. Orders placed before 9:25 will be matched at 9:25 a.m., and the resulting price will be the so-called "opening price." Orders placed between 9:25 and 9:30 will not be processed until 9:30. If the price you ordered cannot be executed on the current trading day, you must re-place the order on the next trading day. Rest days: No trading on Saturdays, Sundays and rest days announced by the Shanghai Stock Exchange. (Generally national statutory holidays such as May 1st International Labor Day, National Day, Spring Festival, New Year's Day, Tomb Sweeping Day, Dragon Boat Festival, Mid-Autumn Festival, etc.)

4. Transaction costs are required for both buying and selling stocks. Commissions (handling fees) are charged. The commissions for buying and selling are determined by each securities firm (the maximum is three thousandths of the transaction amount, the minimum is not limited, the lower the better.), generally: 0.05% of the transaction amount , if the commission is less than 5 yuan, the fee will be 5 yuan. Stamp tax is charged when selling stocks: one thousandth of the transaction amount (previously 3‰, the stamp tax was reduced in 2008, and one thousandth was charged unilaterally).