National expenditure includes

National expenditure represents the total aggregate spending in an economy. It is mathematically calculated using the expenditure method equation for National Income:
$$Y=C+I+G+(X-M)$$

where $C$ is private consumption expenditure, $I$ is investment expenditure, $G$ is government spending, and $(X-M)$ represents net exports. Therefore, consumption, investment, and government expenditure are all vital parts of national expenditure.