Using last weekend's high cup nick fell race as an example, I'd guess that there were 7 or 8 forumites there out of 171 race finishers. Lets assume I was wrong (its been known) and there were actually a dozen people there who are posters on the forum. That means that 7% of the runners at that race were formuites and, from this entirely slap dash survey, I can conclusively prove that any random runner that you might bump into out in the hills has a 93% chance of not being on the forum