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.

A partial government shutdown could cost the U.S. travel industry $1 billion per week and lead to widespread disruptions for travelers, a trade group representing airlines, hotels and other travel companies said on Friday.