TV show - release date - units sold
"M*A*S*H" (Fox, $39.98) - Jan. 8, 2002 - 550,000
"All in the Family" (Columbia TriStar, $39.95) - March 26, 2002 - 125,000
"Cheers" (Paramount, $49.99) - May 20, 2003 - 110,000
"The Mary Tyler Moore Show" (Fox, $49.98) - Sept. 24, 2002 - 85,000
"Green Acres" (MGM, $29.98) - Jan. 13, 2004 - 80,000
"The Dick Van Dyke Show" (Image, $69.99) - Oct. 21, 2003 - 55,000
"The Monkees" (Rhino, $89.95) - May 13, 2003 - 31,000
Source: Video Store Magazine market research
As noted before, M*A*S*H's sales are pretty phenomenal, even adjusting for the low price point. TV shows don't sell on DVD at the level of movies, so most current shows, even the ones that sell well enough for continued releases, don't sell anything like 500,000 copies. Assuming that M*A*S*H's other seasons have sold at the same level, and the rule tends to be that all the seasons of a TV show sell at about the same level if they're all priced the same, then it must be one of the biggest-selling and most profitable shows in the short history of TV on DVD. I don't even like M*A*S*H all that much, even in the Larry Gelbart years; but you've got to admire it for maintaining that level of popularity 30 years after it started, and 20 years after it went off the air.
The biggest disappointment among these sets is probably Green Acres. Sold at a very low price, it sold less than the much higher-priced Mary Tyler Moore. I doubt we'll be seeing any more seasons of the show, which is a shame, because I'd like the chance to buy some of the episodes they did after they went completely insane (the episodes that prompted Dave Foley of Kids in the Hall to describe Green Acres as "one of the most tightly and imaginatively written shows ever done on television"). The Dick Van Dyke Show sold much less than that, but it was a higher-priced set, and done for an independent company with lower sales expectations than a big studio, so all five seasons made it out.