It is tricky to understand this stacked column chart I found here on Twitter, given the negative, below the horizontal axis boxes.

After a bit of studying, I get it (I think). Categories below the axis show a decline. But what does the height of the column above 0 represent, and the height of the total column (the sum of the absolute values of all the boxes).

Eventually, you will figure it out, but “eventually” takes too much time to put in a live presentation.