You mustn’t chop the feet of columns. And you mustn’t hit them on the head either. Have a look.
Source: Hans Zeisel, Say it with figures, New York, 1985, page 128.
This should have been fill columns. But now, it’s only funny. Hans drew it. His book is great. His graphics aren’t. Basically, I’m supposed to understand 5 percent and 8 percent. Instead, I was thinking about the squashed head.