The domestic treasury bond index refers to the SSE treasury bond index. The SSE treasury bond index is a sample of all fixed-rate treasury bonds listed on the Shanghai Stock Exchange, weighted according to the issuance of treasury bonds, with a base point of 100 points. The purpose of the SSE Treasury Bond Index is to reflect the overall changes in our bond market and to be an "indicator" of price changes in our bond market. Just like a stock index, it represents daily price fluctuations. Of course, this index is calculated through the data model. How is the specific model designed? Only the institution that publishes the index knows it. It is an absolute secret, because this index can be sold for money and is intellectual property. Many financial derivatives need to be linked to this index, such as Treasury bond futures.