The specific calculation of the day's profit and loss was written last time, and you also saw it. Now use popular words to explain your problem, I hope you can understand it this time. Your first question: But when there are so many transactions, how do you bring them in? A: This is very simple. We divide the general formula into two steps. The first part is ∑ [(selling price-settlement price of the day) * selling quantity]+∑ [(settlement price of the day-purchase transaction price)] * buying quantity. This is the calculation of closing profit and loss. So no matter how many transactions you make on the same day, as long as you sell, you put the first one in and the second one in. ∑ means addition. You should know that. The second part is (settlement price of the previous trading day-settlement price of the current day) * (selling positions of the previous trading day-buying positions of the previous trading day). This is equivalent to the calculation of historical position profit and loss, that is, summarizing all the sold quantities-summarizing the bought quantities. Question 2. What's the difference between closing price and settlement price and opening price? A: The closing price is the same as the closing price of the stock, which is the last transaction; The settlement price is different. It is divided into trading day settlement and delivery day settlement, because it is the final price of futures settlement, and your profit and loss are related to it, not the closing price. It should be emphasized here that the settlement price calculation of the final delivery date is different in different countries. For example, CME uses the opening price on the settlement date, while Hong Kong uses the average price of the spot HSI on the last trading day every five minutes.