Movies are big business, there is no doubt. But just how big might come as a surprise to some. Just like any business, in order to calculate profit, we must factor in expenses and subtract that from revenue. Some of Hollywood’s biggest sellers in terms of profits might surprise the movie-going public.

Here is a list of the six biggest grossing movies of all time, adjusted for inflation:

1.    Gone with the Wind– The 1939 four-hour epic about the Civil War based on the best-selling book by Margaret Mitchell, set in the south. It won eight Academy Awards. Adjusted for inflation the move grossed $1.78 billion.

2.    Star Wars- In 1977 Star Wars touched something ephemeral in the movie-going public, helping it to rake in a cool $1.58 billion in gross sales.

3.    The Sound of Music- The beloved 1965 musical is based on a true story of the Von Trapp Family Singers and their escape from Nazi-occupied Austria. This heart-warming musical grossed $1.23 billion.

4.    E.T.: The Extra-Terrestrial- One of Steven Spielsberg’s early smash-hits, the story of a sensitive boy and his companion alien won the hearts and minds of a generation in 1982. It showed at the box office with a lovely $1.22 billion in receipts.

5.    Titanic- A film of titanic proportions, this film of epic proportions won 11 Academy Awards. Based on the true story of the catastrophic sinking of the luxury ocean liner Titanic in 1912, James Cameron made the film so that he could go to the site of the sinking and see it with his own eyes in a modern, mini-submarine. This film’s gross take of $1.22 billion is truly titanic.

6.    The Ten Commandments– Based on the biblical story of the exodus of the Hebrews from slavery in Egypt to the receiving of the Ten Commandments at Mount Sinai, who’d a thunk it, that Moses and his rag-tag collection of Jewish ex-slaves could pull in a lovely $1.13 billion? Released in 1956, Cecil B. DeMille’s classic film won the Award for Best Special Effects at the 29th Academy Awards.