|Viv, thanks for your message in the forum.
It is actually quite a difficult problem - mixed monos and cats - handicapping. The Portmouth System works fairly well but is tough on smaller/older classes which don't get enough returns, and it is in no way "international". As I have said in my message/reply to Ian, because the RYA will not divulge past years Portsmouth numbers the only solution is to acquire this data by shopping around and build up a database. This will allow people like myself, to sail in non-ISAF races as well.
Just sending my BHCCA sub off to you. I used to live down your way - on, up river between the Stone and Stansgate, small private estate called Scarletts, built by my grandfather and friends, between about 1900 & 1910, for holidays and weekends, on land bought from a farmer called Scarlett - now there's a thing!
Best wishes, Nick