Estimating how much pension a person is due from working one year, even though the person might not receive the pension for many years, is an example of accrual. In government, much of the accounting and financial reporting is geared to things that will happen and involve cash during the fiscal year. Government audits include not only adherence to GAAP, but also government laws and regulations. These people will be paid the interest rate stipulated, and, if they hold the bonds to maturity, they will get the principle too. Bonds can be traded prior to the maturity date, but the amount received will depend on a comparison between the contract interest rate and the market or current interest rate for bonds with similar risks.
Bonds usually have a principle amount and a contract interest rate.
The principle can be paid at maturity while the interest is generally paid semi- annually as a percent of the principle. These bonds would be called term bonds , since they are due at a fixed point in time. Serial bonds come due at different points in time. The budget covers the governmental decisions on how to raise money and where to spend it. Traditionally, one of the most public decisions in government.