Doonesbury by Garry Trudeau for March 24, 1971
Transcript:
Mike: Say, Dad, B.D. and I have decided to go skiing at Vail this spring vacation...What? Well, Dad, I know you want me to come home, but...now, c'mon Dad! I'm twenty years old! I'm growing up, and if I feel like going skiing, then I'll go! I'm not coming home! ...Oh, ah, Dad? I'll need a hundred dollars.
Vail on $100???? This WAS a long time ago.