Principles of Macroeconomics/Macroeconomic Principles/Calculating GDP

2.3 Calculating GDP: Expenditure and income approaches
It is important to keep in mind that this section details the computational method for calculating total output in the economy using income. Income is the other side of the national income accounting process. For a country (or household) to be efficient, it must be able to detail the sources of its income. The point of the national income accounting system is to determine efficiency of a country, much like one would do in one's own household. Economists seek data about income as well as expenditure; ideally, the two should be in balance - that is, they should be the same amount. When income and expenditure are balanced, the country or the household is said to have a balanced budget.