The data for this plot comes from Coursera's Applied Plotting, Charting & Data Representaion in Python course offered by University of Michigan. To avoid breaking the honor code of Coursera, I kept the code private.
Note: On the plot, there are columns of dates. Although the columns seem to overwhelm the plot, I kept them anyway as the main goal of making this plot is learning and the code for annotating the plot was worth keeping.