What is the most recent television show where the entire main cast has died?

[TMC]

This is an offshoot of sorts of the thread on older actors who outlived their younger castmates.

*Bewitched (it went off the air in 1972), unless you count Erin Murphy, who was Tabitha. But all of the adult cast-members (Elizabeth Montgomery passed in 1995 while Dick York and Dick Sargent passed away in 1992 and 1994 respectively) as far as I know are now deceased.

*Barney Miller (which went off the air in 1982) is getting awfully close. With Abe Vigoda finally passing, that just leaves (if I'm not mistaken) Hal Lindon, Max Gail, and Gregory Sierra.

*The original Hawaii 5-0 ended in 1980, and everyone from that is long gone.

*Different Strokes (which ended in 1986), with Charlotte Rae's passing 2017, that makes Todd Bridges the only of the original cast still alive.

*Highway to Heaven (which ended in 1989) had only two billed regulars: Michael Landon and Victor French. And both stars were dead within three years by cancer.