Actually, I believe it's the other way around - the higher number the better. I remember seeing that I was a "5" at the Vienna Danube when I was asking the breakfast room supervisor about complementary breakfast for my parents and myself during an award stay after getting the runaround from the front desk since I had not been "upgraded" (it's an either/or deal there on award stays - upgrade or breakfast).

Almost everybody (mostly tour bus patrons) had a 0 or 1, there were a couple of 2s and 3s, and then I was the only 5 out of about 60 rooms that I was able to scan. The supervisor said "oh, you're a level 5, of course you get breakfast!" and that was that.

I couldn't figure out why Diamond was a 5, I think I came up with:

0 - Group rates
1 - Regular booking non Honors
2 - blue
3 - silver
4 - gold
5 - diamond