Forex industry average demo to live conversion ratio?

Hello everyone, I want to make a presentation for my MBA that has to do with the forex market. Can anyone point me to a reference that shows statistics or info about the demo to live conversion ratio for forex brokers?
Ive searched for hours via google and the only thing I found was quarter reports of brokers (mainly regulated like FXCM, GAIN etc), but these only have accounts, volumes and not conversion rates…

Very hard to find these info. Check Oanda website. I remember they have some info.