Always add a title and source info to your chart.
Always add a title to your chart. This ensures that everyone, no matter if they know the data or not, understands what is presented on your chart. We've already discussed what makes a good title when we looked at the scatter plot; the same applies here.
And once again, adding the source of your data to your chart makes it more credible.
To add this information to the chart, use the following command:
+labs(title="your_title", subtitle="your-subtitle", caption="your source")
Obviously, you'll add your own title, subtitle, and source info where the placeholder texts are. Don't forget the double quotes!