How long it usually takes for cinemas to keep showing a film?

If a film is popular ( like Harry Potter) how long will it last on screens? Can it reach to 2 or 3 months?|||yeah the average is 6 weeks nowadays since the like to get dvds and on demand going around 2 months from the release date. So you can find a movie in the theater 2 months down the road it just won't be in wide release anymore or at major "Brand Name" theaters.|||Movies that are not popular are on for at least 2 weeks but the show times can be drastically reduced the 2nd week so that it might be only twice a day when it might of been five or so the first week.Popular movies pretty much keep going till they stop making the theatre money,could be months but depends on the size of the cinema and how many new movies they might get.|||It has been so long since I watch any of the movie but recently planned for new movie