I am not asking about post credit scene; I am asking about bloopers. I've done research and found "Rush Hour (1998)" is the first movie to show bloopers at the end of the movie. Are there any older examples than this movie?
Another site listed Hooper (1978) with Burt Reynolds, as being the earliest example of this in a movie. This makes sense because the wikipedia article on bloopers does credit Burt Reynolds and Jackie Chan with being known for putting bloopers in their ending credits.
I will update if I am able to find any earlier examples. Also I should mention that the wikipedia article mentions the earliest known "bloopers" to have been popularized on tv and radio as early as the 1930's, but the question specifically asks for the first movie to show bloopers at the end of the movie (ie in the credits) so I've limited my answer to that criteria.