To look ahead toward the final exam, we reviewed the algebra of our stock pricing theory.

Adding an aggregate supply function lets a build a theory of business cycles caused by shifts in the AD curve.

The Phillips curve data (see handout) support a Keynesian view up to about 1969. Events in the 70's and early 80's do not look particularly like cycles caused by AD shifts.

That data actually looks more like the result of supply shocks.