Yes 1986 was deleted as well.
Somewhere in my emails, I'm sure there is one that says: If a sticker is removed, and you have a blank, the other side [the back becomes the card now]. and where the sticker was is now blank. So the following fit that criteria. I guess thats how the Sticker Back Sets were listed. Personally I don't see anything wrong with it, much easier than Ed's explanation [sorry, site's explanation]. Topps, Fleer, Panini whatever. Wait till you see the Basketball mess.
It really doesn't matter to me either, other then I collect stickers and have all the sticker back sets. If the sticker back sets aren't "listed" per se,they can be in many different ways on here. Shame we have to go those routes. I think each of the following sets are pretty neat.
'80-'81 - Record of All All-Star Games and All World Series Games
'82 - NO set - Puzzle Backs
'83-'84 - Stats and Season Totals
'85 - NO set - Ads
'86 - Famous Feats
'87 - Team Logos
'88 - Team Stadiums
'89-'91 - Team Trivia etc.
At the moment it is what it is.