Each summer since the Delacorte's opening has seen between one and three works produced, with two works being standard since 1973. The plays of Shakespeare account for about four-fifths of the works produced, and, except for 1977 and 1980, each summer's line-up has included at least one work by Shakespeare (or, in the case of 1970, one work adapted from Shakespeare). Non-Shakespeare productions have included plays such as Anton Chekhov's "The Seagull" and Henrik Ibsen's "Peer Gynt" and musicals such as "On the Town", "Into the Woods", "Two Gentlemen of Verona", "The Mystery of Edwin Drood", and Disney's "Hercules", the latter three having made their world debuts at the Delacorte.