This is from the Robin Williams site I'll link below- maybe it helps?
"Williams had a good deal of success with stand-up during the 1970s...After performing on the revival of the Laugh-In series in 1977-78, Williams landed a guest role on the popular sitcom Happy Days as Mork,...to his own spin-off sitcom, Mork + Mindy (1978-82)...With a successful sitcom under his belt, Williams also brought his talents for improvisation and stand-up comedy to cable television, headlining two Home Box Office (HBO) comedy specials,
An Evening with Robin Williams (1982) and
Robin Williams: Live at the Met (1986). In 1986, he joined fellow comics Billy Crystal and Whoopi Goldberg in hosting HBO's annual Comic Relief telecast, which donated all funds raised to helping the homeless..."
Here's the reference site- note, all of Robin Williams' profits from sale of merchandise here goes to profits...
http://allstarz.hollywood.com/robinw.../biography.htm