Aggregate Demand and Aggregate Supply

This chapter introduces the Aggregate Demand/Aggregate Supply model of macroeconomics. Read the introduction and Section 1 to learn about Aggregate Demand and the three effects (weath, interest rate, and international trade) that cause the downward slope. Recall the difference between quantity demanded and demand - the same logic applies to Aggregate Demand. Identify the variables that change (shift) the Aggregate Demand curve. Read this chapter and attempt the "Try It" exercises. You will revisit certain sections of the chapter later in this unit.

Aggregate Demand


  • Potential output is the level of output an economy can achieve when labor is employed at its natural level. When an economy fails to produce at its potential, the government or the central bank may try to push the economy toward its potential.
  • The aggregate demand curve represents the total of consumption, investment, government purchases, and net exports at each price level in any period. It slopes downward because of the wealth effect on consumption, the interest rate effect on investment, and the international trade effect on net exports.
  • The aggregate demand curve shifts when the quantity of real GDP demanded at each price level changes.
  • The multiplier is the number by which we multiply an initial change in aggregate demand to obtain the amount by which the aggregate demand curve shifts at each price level as a result of the initial change.