The data doesn't look very accurate. For one thing, this data doesn't appear to represent what companies pay.
I usually get bill rates up around $100/hr to $150/hr depending on skill and location. Like New York has higher cost of living than Michigan so I can often pull a higher bill rate.
The payout to the H1B is works out to be $60K to $80K. An Oracle DBA working in New York will make about $80K which is roughly $38/hour and the company easily pays $125/hour for 6 month contract.
I have some overhead but it's usually a one time fee such as transferring H1B from one company to mine, legal paper work to renew, attain, and transfer H1Bs runs me about $500/piece.