Call auction has a ceiling of 20% on the first day of listing and 20% after opening, so the biggest increase is 44% of the issue price.

First, the trading rules of Shanghai and Shenzhen Stock Exchanges stipulate that the maximum increase on the first day of issuance is 44%, and all securities trading participants must abide by this game rule.

2. Article 62 stipulates that the exchange shall impose price fluctuation restrictions on stock and fund transactions, with the fluctuation ratio of 65,438+00%, of which the fluctuation ratio of ST stock price is 5%. The calculation formula of price fluctuation is: price fluctuation = previous closing price × (1 price fluctuation ratio). The calculation result is rounded to the smallest unit of price change. Stocks and funds are not subject to price limits on the first day of listing. When the Exchange deems it necessary, with the approval of the CSRC, it may adjust the proportion of price increase and decrease and the scope of application.

Third, the listing of new shares must rise sharply, not necessarily. This is mainly determined by the current market and everyone's expectations of stocks.