Generally speaking, the stock exchange stipulates that the daily fluctuation range of stocks in the A-share market is 10%, and the daily fluctuation range of stocks starting with S or ST is limited to 5%. If the stock rises today and reaches the highest 10%, this is the daily limit. If it falls, the maximum limit will be-10. A stock that starts with S or ST will not go up when it rises to +5%, and it is also a daily limit. If it falls by 5%, it is a daily limit. There is no restriction on the first day of new listing. This law is the characteristic of China stock market.
The full name of stock index futures (SPIF) is stock index futures, which can also be called stock index futures and futures index. It refers to the standardized futures contract with the stock price index as the subject matter. The two parties agree to buy and sell the underlying index according to the size of the stock price index determined in advance at a future date, and settle the difference in cash after the expiration. As a type of futures trading, stock index futures trading has basically the same characteristics and processes as ordinary commodity futures trading. Stock index futures are a kind of futures, which can be roughly divided into two categories, commodity futures and financial futures.