The most important national income totals are Gross Domestic Product (GDP) and Gross National Income (GNI).

According to the circular flow of economic activities:

• the value of production (value of goods and services produced) is the same as the value of the factors of production used to produce the goods and services, and
• the income received by households is the same as the income that was spent.

These four values are the same because we assume that all income received is spent and that all products produced are sold.

The difference between the concepts domestic and national is that:

• domestic means within the borders of a country (even if foreign factors of production are used), and
• national means the factors of production owned by South African citizens, wherever they may be in the world.