On the question - Should it not be 80%?

That's purely dependent on ecconomics. If large health purchasers pay extremely well then the number could be 0%. If they pay rates well below that which the market will accept then I'd expect a high figure. In Victoria, I suspect (entirely on anecdotal evidence) that the figure should be higher however other factors holding physiotherapists back such as concern about the reaction from GPs and patients are more of a factor then awareness at the moment. Importantly, if this number increases substantially over the coming year or so, it will present some challenges to large purchases who try to argue that their prices are in line with community expectations.