Graph for output (real gdp) on the horizontal axis, label it as "real gdp." on the vertical axis, label it as "price level" or "p." draw an ad-as graph. plot the ad (aggregate demand) curve. assume that it shifts rightward from 2019 to 2020 and then shifts leftward from 2020 to 2021, indicating changes in aggregate demand. plot the as (aggregate supply) curve. if the economy is facing supply shocks like the covid-19 pandemic, as may shift to the left in 2020 and then adjust back to the right in 2021. keynesian economics