I've been reviewing posts on Stack Overflow since before the new Reviewer badge and stat tracker was brought in.
I assume it isn't possible to retrospectively update the review stats as the necessary code didn't exist at the time? Unless it is a bug, in which case it would be great if the stats could just be updated.
If not, I understand the difficulty in working out the exact number of previously reviewed posts, but is it possible to take into account something like flag history?
For example: I have flagged over 100 posts through the review process, which would already be past half way to the 200 actioned mark necessary to attain the badge.