Free US Law Dictionary

Gross National Product

Measures of national income and output are used in economics to estimate the welfare of an economy through totaling the value of goods and services produced in an economy. They use a system of national accounting first developed during the 1940s. The primary measures of national income and output are Gross Domestic Product (GDP), Gross National Product (GNP), Gross National Income (GNI), Net National Product (NNP), and Net National Income (NNI).

There are three main ways of calculating these numbers; the output approach, the income approach and the expenditure approach. In theory, the three must yield the same, because total expenditures on goods and services (GNE) must equal the total income paid to the producers (GNI), and that must also equal the total value of the output of goods and services (GNP).

However, in practice minor differences are obtained from the various methods due to changes in inventory levels. This is because goods in inventory have been produced (therefore included in GNP), but not yet sold (therefore not yet included in GNE). Similar timing issues can also cause a slight discrepancy between the value of goods produced (GNP) and the payments to the factors that produced the goods, particularly if inputs are purchased on credit, and also because wages are collected often after a period of production.