Thank-you all.

I've had this data for 10 years now, maybe I copied it from someone's SQL 2000 book - or possibly it came from an SQL 7 course I did (in 1999!), and I found it really useful, But I was slightly unsure that it was still valid, particularly as I had some difficulty in finding a concrete reference.

Thanks Paul for the tip on Itzik's book - I'll be visiting Amazon soon I think (or should I wait for the R2 edition?)