For balance have a look at the latest
DASA Stats which includes all ranks (and if you can be bothered to search their site it has all sorts of other interesting facts (!), including VO stats (previously known as PVR))
Do we really have 1150 WO/MACR?
Sadly, because of JPA (what else!) the latest Army stats are not available. However, the Navy stats are there - surprising to see that even as a smaller Service than the RAF they have more Senior Officers than Junior.