I think you need to get the most accurate data re: how much your health care and other fixed fringe benefits cost your agency so you can make an educated appeal

I think you need to get the most accurate data re: how much your health care and other fixed fringe benefits cost your agency so you can make an educated appeal showing that you recognize you're willing to see a calculated and reasonable decrease in your hourly compensation. Then you need to consider if your agency is going to be able to generate the same number of billable hours if you cut back. If they can't without hiring someone else, I've seen some success when two people offer themselves up as a paired unit where between their billable time and fringe benefit expenses, they still offer a net benefit (or at least not a net loss for the employer).