Okay, so I read the report and they seem to think that it's worth €4.6k for each adult and €1.6k for each child to be involved in the GAA. And then counting the happiness the volunteering gives, along with the previously counted monetary saving of having volunteers is with roughly €5k per volunteer.
Not sure who's saving the money, or how, or how they came to the valuations, but they have numbers on it.
Interesting document - cheers OP.
Congrats, I read it as horse first time round, either way, best of luck!