What was the most successful American business of the 20th century?

Question

A business magazine wrote an article in the late 1990's. They calculated the total profits of businesses and subtracted the overhead and other costs. They had a Top 100 list. I believe that fast food was number 10. Automobiles were farther down on the list due to the cost of design. Does anybody remember the number one business? Can you guess it? I can't remember it.

Answer 1

I'll bet you it was I-Pods, lap top PCs, or automatic car starters.

Answer 2

oil companies

Answer 3

banking