1, the market interest rate is negatively correlated with the expected yield of national debt. The decline of national debt means that the market interest rate rises;

2. Supply and demand also affect the rise and fall of national debt, which means that the supply of national debt in the market is greater than the demand of investors;

3. If a country's economic prospects are not optimistic, the possibility of default increases, and the country's credit sovereignty declines, foreign capital will sell the country's national debt and withdraw, leading to its decline.

National debt, also known as national debt, is a creditor-debtor relationship formed by the state on the basis of its credit and in accordance with the general principles of debt. National debt is a bond issued by the state, a government bond issued by the central government to raise financial funds, and a debt certificate issued by the central government to investors, which promises to repay the principal and interest within a certain period of time. Because the issuer of national debt is the country, it has the highest credit and is recognized as the safest investment tool. Types of national debt: China's national debt is divided into voucher-type national debt, bearer (physical) national debt and book-entry national debt.

1. Voucher-type national debt refers to the national debt issued by the state by filling out the receipt of treasury bills, rather than printing physical bonds. It is in the form of treasury bonds receipts as creditor's rights certificates, which cannot be listed and transferred, and interest will accrue from the date of purchase. During the holding period, if the holder needs to withdraw cash under special circumstances, he can redeem it at the purchase outlet in advance. When redeeming in advance, in addition to repaying the principal, interest is calculated according to the actual holding days and the corresponding interest rate grade.

2. Bond bearer is a kind of physical national debt, which is issued by recording creditor's rights in the form of physical bonds (year of issue, bond amount, etc.). ) If the name of the creditor or the name of the company is not recorded on the face, it is also called a real bond. It is the longest issued national debt in China.

3. Book-entry treasury bonds, also known as paperless treasury bonds, are accurately defined as bonds that are issued by the Ministry of Finance in a paperless manner, record creditor's rights by computer bookkeeping, and can be listed and traded.