Profit percent price chart
Obviously, lots of people had problems calculating percentages back in 1936 too. It’s not just a new problem with our educational system.
You may notice a big jump after this page. This is page number 2412. The next number is 2500.
The catalog was built back in the day before computers and everything had to be typeset. So the gap between page 2412 and page 2500 is obviously where they left room to insert more pages of products. They couldn’t know ahead of time exactly how many pages they would need and everything had to be set up well in advance.