It's interesting to see the differences. Have to say I've never fully understood Air Watts vs motor wattage, being bought up with motor watts only on display.
Looking at your list though, it seems to me that design has as much to play with air watts as power, going by the machines I have expereience of on your list:
DC01-90 AW - 1000w
DC02-90 AW I think - 1200w?
DC03-90 AW - 750w
DC04-230AW - 1200/1400w
DC05-255AW - 1400w
DC07-330AW - 1400w
DC08-330AW - 1400w
DC11-330?AW - 1400w?
DC14-290AW - 1400w
DC15-? - 1200w?
DC19/20...- 290AW (my DC22 is 1200w)
DC24-120AW - 650w
DC25-220AW - 1200w
Interesting how all the 1200w machines have different air watts, although probably not surprising. We all know the DC02 isnt the last word in refined design, and the cyclone assemblies differ greatly between all the models.
I want one of those air meter things I've seen the Americans bang on about on Vacuumland, that could provide interesting geeky statistics, comparing a 350w Junior against a 2200w Miele etc