(1) The "327" treasury bond futures event started from June 1994 to June 10. The People's Bank of China raised the interest rate of savings deposits with a term of more than three years, resumed the value-preserving subsidy, and China bonds also enjoyed the value-preserving subsidy and discount. As the value-added subsidy rate is published once a month, there is great uncertainty, which provides rich imagination for the speculation of treasury bonds futures. A large amount of funds began to flow into the national debt market, and the national debt futures market became increasingly popular, with the continuous expansion of trading volume and increasing market positions. However, the focus of the confrontation between long and short sides has always been the prediction of the maturity price of "327" government bond futures.

The national debt corresponding to the "327" national debt futures contract is a three-year national debt issued by 1992. The coupon is coupon rate 9.5%, with a term of 3 years, and the principal and interest will be repaid once at maturity. If there are no value-added subsidies and discount factors, then the maturity price of the coupon should be the sum of the face value 100 yuan and the accumulated interest for three years of 28.50 yuan, that is, 128.50 yuan. However, due to the implementation of value-added subsidies and interest subsidies, the maturity price will be affected by the above two factors. However, before the Ministry of Finance issued an announcement on February 26th 1995, which clearly stipulated the specific measures for the implementation of value-added subsidies, the market did not reach an understanding on this. Both long and short sides opened positions near 148 yuan on a large scale, and the positions of "327" varieties not only expanded sharply, but also concentrated in the hands of a few institutions, so the market risk is imminent.

1On February 23rd, 1995, the Ministry of Finance issued an announcement on the issuance of 1995 new treasury bonds. Due to the fact that 1995 new treasury bonds have less tradable parts, and the news of 1992 three-year treasury bonds' preservation, subsidies and discounts has gradually become clear, the situation is obviously beneficial to many parties. The major national debt futures markets have stepped out of the upward breakthrough market. However, the Shanghai government bond futures market failed to close at the price of "327" contract 148.50 yuan, which further induced the market to soar sharply, causing heavy losses to short sellers.

In order to reduce losses and violate the market trading rules, the former Shanghai Wanguo Securities Co., Ltd. adopted the overdraft trading method, and sold10.56 million orders within 8 minutes before the closing of the exchange in the afternoon, reducing the contract price of "327" from 150.30 yuan to 147.50 yuan. The contract price of "327" plummeted by 2.80 yuan in 7 minutes, which caused the multi-party positions opened on the same day to explode (that is, the trading margin was completely lost). On that day, the turnover of treasury bonds futures on the Shanghai Stock Exchange reached a record 853.6 billion yuan, of which "327" contracts accounted for about 80%. This intentional violation by the main air force has caused serious consequences and bad market impact. In order to avoid further expansion of the situation, the Shanghai Stock Exchange announced that the last 8 minutes of trading was invalid, and the market was closed from February 27, and the OTC agreement was closed.

(b) "319" Treasury futures event

The "3 19" incident is another vicious violation of regulations in China's futures trading market after the "327" incident. The cause and operation of this incident are quite similar to the "327" incident.

On May 1995 and 1 1 day, the "3 19" variety in the Shanghai government bond futures trading market opened at the daily limit of 183.88 yuan. Before the closing of the day, the main short sellers with serious losses used a large number of overdraft transactions, backlog and other illegal means, which led to large fluctuations in the trading market. On the same day of the "3 19" contract, the turnover reached 1.73 million lots, and the position reached 570,000 lots. Due to the sudden increase of market risk and serious violations of short positions, the Shanghai Stock Exchange suspended the opening of new positions on May 2 12, and took measures to forcibly close the positions of member units by 50%. On that day, the members closed 460,000 positions, accounting for more than 50% of the total positions held in May 1 1 day.

On May 15, the Shanghai Stock Exchange resumed the trading of treasury bonds futures, and announced that five members who violated the rules would be severely punished for stopping the trading of treasury bonds futures and fined.

On the afternoon of May 17, one week after the "3 19" incident, the China Securities Regulatory Commission announced that it would suspend the trading of the national debt futures network. China government bond futures trading ended in failure after 404 trading days.