plaque number means nothing other than being unique. if the registars are vaugely accurate, there's huge number blocks missing.
at the time i got mine (#3105), it was 500 more than the next known, and remained one of the highest for 6months with even new deliveries months later coming in lower than mine. this is all taken from forum activity.
not sure about global, ITR 8k, uk was 2.5k sold. no idea how many remain.