Found what I was looking for here:

PRINTING AND DISTRIBUTION DATA
https://www.splintercards.com/tool-distribution.html

Over the next little while I am going to put together a list of scarce cards that present some investment value. With Chaos Legion about to open up I suspect those cards will go down in value with the extra supply hitting the market. I will be focusing on some of the older packs where there are much less cards in circulation.