I don't know the exact numbers for this case, but contractors always appear to be overpaid. What most people who call them overpaid miss is that contractors have to pay their own employment taxes, as well as any health benefits (including vacation time) they want out of that income.

If you consider those, the cost of your average employee to the company employing them is roughly 1.6x to 2x their gross income. An overpaid contractor would have to make well over 2x that of a normal employee.