Hi Folks...after my original post and your responses, I decided to make another plot and see if it was all informative. I took Detective 1-40 and plotted total CGC graded copies (all books...universal, restored, qualified, etc.) along with the Gerber Scarcity value. See the result below.
To be honest...I am not sure this says anything meaningful. I had suggested before that I thought the issues prior to 27 were not graded as often as those after 27. This data clearly shows that to be true. But it's hard make the conclusion that those issues are actually rarer with a lot of confidence. For the really early issues, there may not be that many raw books out there...or maybe there are. It's hard to say. As an example, Gerber says that issue 2 and 3 are really scarce...and that agrees with the CGC data to some extent. But the other books don't seem to correlate very well with that idea. (Maybe 24...but that would be it)
Anyway...just thought I would throw this out there. I will put it up on my blog for reference as well.
Cheers...