The net value of fund units is the net asset value of each fund unit, which is equal to the balance of the total assets of the fund minus the total liabilities divided by the total number of units issued by the fund. The subscription and redemption of open-ended funds are carried out at this price. The transaction price of closed-end funds is the market price that has been confirmed at the time of transaction; In contrast, the unit transaction price of open-ended funds depends on the net asset value of unit funds that are not known at the time of subscription and redemption (but can be calculated after the market closes on the day and announced on the next trading day).

National debt, also known as national public debt, is the relationship between the creditor's rights and the debtor's rights formed by the state, based on its credit and according to the general principle of debt, by raising funds from the society.