You're asking a question about language use here, yes?
Depends on the context.
If 90% of U.S.voters voted for a particular policy proposal I would comfortably describe that as a "vast majority", but if only 90% of sulfur atoms remained in an unstoppered container of sulfur at STP I would describe that as a "startlingly small percentage".
On a minute's thought, I'd say 2 standard deviations above mean portion-size for the context under discussion.
If it's worth saying, but not worth its own post, even in Discussion, it goes here.