Which reviews are rarer than others?
I think that late answers should be the rarest but I want a order of rarity of them.
At the time of writing, the global number of reviews done was:
Personally, I was a bit surprised that First Post is that high in the list. Subjectively, I would have thought it below Low Quality and closer to Reopen.
It should be noted that the criteria for reviewing sometimes change, which can change the current number of reviews relative to the global number.