The consumption function is one of the most important concepts in Keynesian economics. It describes the functional relationship between consumption expenditure and income. Keynes emphasized that consumption depends mainly on current income and plays a crucial role in determining aggregate demand and employment in an economy.
The consumption function refers to the relationship between consumption (C) and income (Y). It shows how consumption changes as income changes.
C = f(Y)
It means consumption is a function of income. As income increases, consumption also increases, but not in the same proportion.
According to Keynes, consumption increases with income but at a diminishing rate. This means that the marginal propensity to consume (MPC) is less than one.
At low levels of income, most of the income is spent on consumption, and savings are very low. As income increases, the proportion of income spent on consumption decreases, and savings increase.
The consumption function is generally stable in the short run, and it plays a key role in determining aggregate demand in the economy.
Consumption curve lies below 45° line showing MPC less than 1
The consumption function explains how consumption depends on income and is a key determinant of aggregate demand. Understanding its behavior is essential for economic policy and growth. By influencing the factors affecting consumption, governments can stimulate economic activity and employment.