This is an interesting link.
http://www.payscale.com/research/US/...er/Hourly_Rate
I certainly will not be giving up my day job based on this. Even for a photographer of 20 years experience you would only be earning the equivalent of a graduate in my area of work....and you have to fork out the cash for equipment, insurance, travel etc. etc. Even with the commission value quoted for a 20 yearer ($10,000) it is pocket money. How do photographers make ends meet? It gets worse because the figures quoted are at the top end of the scale. I have never looked at this before and I must say I am quite shocked.