The U.S. Department of Health, for example, has in place a contingency plan for agency operations during a government shutdown, with 49,625 staff members considered essential and 40,887 staff members being furloughed, which breaks down to 55% retained and 45% furloughed.

Lawmakers have until midnight Friday to pass a bill or risk shutting down the government before they embark on a 16-day break

If Congress fails to approve a continuing resolution or permanent spending measure by 12:01 a.m. Saturday, many federal agencies and services could be shuttered. Their closures would force hundreds of thousands of employees to be furloughed or sent home just before the holidays.