Marginal Propensity to Consume

Proportionate change in consumption due to change in income will be same (Positively)

$$\begin{array}{rl}MPC& =\text{Marginal Propensity to Consume}\\ & =\frac{\Delta C(\text{Consumer Spending})}{\Delta Y(\text{Disposible Income})}=\frac{\Delta C}{\Delta Y}\end{array}$$

Also, Marginal Propensity to Save