In a previous article, (Rich) said:
I once spoke to a flying club member who said that the availability of
their club aircraft improved with 30 members and three aircraft
compared with 15 members and only two aircraft.

Is there any kind of mathematical formula that could take into account
the number of aircraft, the number of pilots, and predict what the
average aircraft availability would be? I imagine that fractional

Probably not, since flying hours per member varies with the economy.

Back when our club was nearing 15 members per plane, it was getting damn
hard to schedule a plane when you wanted. But the reason we had so many
members was the same reason the members we had were flying more hours than
usual - the economy was booming, and people had more money. Now we're
down to 11 members per plane, and the members we have aren't flying as
much, and it's much easier to get planes. Back then we put on 300-400
hours per year on each plane, this year some of our planes are going to be
lucky to break 150 hours, and one of them got a new engine in June and we
still haven't done 50 hours of break-in.

--
Paul Tomblin http://xcski.com/blogs/pt/
"The means of defense against foreign danger historically have become the
instruments of tyranny at home." - James Madison