The four posters are for the original productions of musicals A Chorus Line, Cats, 42nd Street and The Mystery of Edwin Drood. Three of the shows had long runs that encompassed most of the 1980s, but Drood ran only Dec. 2, 1985-May 16, 1987. The poster also trumpets the latter show's Tony Award as Best Musical, which it received in June of 1986. That means the posters were likely put there sometime between summer 1986 and spring 1987.
This photo is used here with permission from Brian Busby.