he consumption function from the MPC Consider a hypothetical economy in which the marginal propensity to consume (MPC) is 0.50. That is, if disposable income increases by $1, consumption increases by 50t. Suppose further that last year disposable income in the economy was $400 billion and consumption was $300 billion. On the following graph, use the blue line (circle symbol) to plot this economy's consumption function based on these data. 700 O 600 Consumption Function 500 400 300 O CONSUMPTION (Billions of dollars) 200 100 O