The Stock Market Boom of 2015, Imagine that in 2015 the economy is in long-run equilibrium. Then stock prices rise more than expected and stay high for some time. Refer to Stock Market Boom 2015. In the long run, the change in price expectations created by the stock market boom shifts. Which curve shifts and in which direction? a. aggregate demand shifts left. b. aggregate supply shifts left. c. aggregate demand shifts right.d. aggregate supply shifts right.