Speaking from experience and having seen a few of these data points personally (possibly over-indexed on a small amount of data), often this comes down to making a choice of 220 with a 50% utilization vs 165 with 70%. Pretty much the same revenue for the company in the end, but with enough slack to put some extra short term gigs in there. Alternatively, in a situation where the company is confident of higher utilization, getting long term work, locking in a higher rate later, or being able to add extra bodies to the contract this is about $130 at 90% utilization (52 weeks - 4 weeks leave - 2 weeks public holidays). All these are common in .au govt contracts.

The mentioned 80-120 range seems like a feasible answer to this. Push for more (or strong bonuses) if utilization is generally high. Obviously the 140% depends a bunch on location / taxes / cost of doing business etc., find out what these are in your neck of the woods and exploit it to negotiate your salary.