An Oscar Trivia Question

Only three films have ever collected all of the top four Oscars (best picture, actor, actress, and director), namely It Happened One Night (1934), One Flew Over the Cuckoo's Nest (1975), and The Silence of the Lambs (1991). But usually a film which gets one of these will get at least one more. For example, at Sunday's Oscars, Million Dollar Baby collected three of the top four awards (picture, actress, and director) and in 1998 Shakespeare in Love collected two (best picture and actress). It has been a long time when each of the top four went to different films. When was that?