2. The fuse of US stocks can be divided into three levels. When the Standard & Poor's 500 Index falls by 7%, it will trigger the primary market to fuse and interrupt trading 15 minutes. When the Standard & Poor's 500 Index falls 13%, the secondary market will be blown and trading will be interrupted 15 minutes; When the S&P 500 index fell by 20%, all-day trading ended early. On the basis of primary and secondary market fuses, there will be no two fuses of the same level within one day. In non-American time, when the stock index futures price reaches 5%, no futures contract with a price increase of more than 5% can be traded.
3. Market fuse mechanism This means that a major stock or commodity exchange temporarily stops trading, because an index, or even a stock, has fallen by a certain percentage in a trading day. Its purpose is to prevent the market or stock price from falling freely by rebalancing the buying and selling orders. For example, if the Dow Jones Industrial Average falls by 65,438+00%, the new york Stock Exchange (NYSE) may suspend market trading for one hour. There are other fuse mechanisms that cause 20% and 30% drops. In addition to the market-wide fuse mechanism, the US Securities and Exchange Commission also tried out a market rule on 20 10, allowing the fuse mechanism to suspend the trading of certain securities, and the prices of these securities fluctuated within five minutes 10% or more. This fuse mechanism is suspended for the S&P 500 index; P 500 index, Russell 1000 index, Russell 1000 index and hundreds of exchange-traded products. They suspended trading in all applicable securities in the US market for five minutes.