Rob - our average pass mark is clearly posted on our website - it hasn't really moved from 88% since we started. If people want more in depth info, we are only too glad to provide it, time permitting, i.e. they may have to wait a while while we dig it out!
Our typical figures are 4-6 failures out of 96 exams taken, mostly due to bad planning and running out of time. Only one person has not got his licence yet and that was because he was chopped at the flying stage, well after we had our sticky mitts on him! We've had two people run out of sittings and have to start again, but they still passed. The exact figure escapes me, but over 120 people have passed so far.
The above fugures do not include people who have enrolled and then proceeded not to submit progress tests! Go figure.