Linear consumption function When analyzing the relationship between short-term consumption and income, especially without considering the margin consumption Under the condition of propensity, consumption function It can be expressed as a linear consumption function: C = a + bY

Among them, a and B are constants. In the formula, a is called autonomous consumption, and it is not affected by the change of income. BY is the consumption caused by income, and it increases with the increase of income. The linear consumption function shows that with the increase of income, consumption increases by a fixed proportion of B. At this time, the consumption curve is a straight line tilting to the right.