The NY-Times posted this nice graph, showing for each film how much money it made in the States without showing the numbers.
It covers the period of 1986 till now and, well, just look. It’s very cool.
Amongst other things you can see how much money was made in a certain period, if it was a slow month or not and how much of that can be allocated to a single movie.
But it also shows how long movies were generating revenue. Check “Lion King” or “Saving Private Ryan” and you can see those were in the cinema forever, thanks to some re-releases.

Follow this link: box office chart