The doctrine of at-will employment can be overridden by an express contract or civil service statutes (in the case of government employees). As many as 34% of all U.S. employees apparently enjoy the protection of some kind of "just cause" or objectively reasonable requirement for termination that takes them out of the pure "at-will" category, including the 7.5% of unionized private-sector workers, the 0.8% of nonunion private-sector workers protected by union contracts, the 15% of nonunion private-sector workers with individual express contracts that override the at-will doctrine, and the 16% of the total workforce who enjoy civil service protections as public-sector employees.