If you're referring to the Archie Digests, value is relative to demand, and the market for these books is quite different than that for standard sized comics. Age is mostly irrelevant for these as far as value goes, and even digests from the 70's can be found cheaply unless in pristine condition, so it wouldn't make sense to have a book graded as you'd never recoup the costs involved. With few exceptions nearly all the story material is reprint as well. The only (Archie)digest I can think of that has collector interest from the last 30 years is Archie All-Canadian #1.