The numbers are based upon the sortable list below, which includes further details and references. Note that the holders of certain official positions have been referred to as "czars" for only part of the time those positions have existed. For example, there has been an Assistant Secretary of Labor for Mine Safety and Health since the passage of the
Mine Safety and Health Act of 1977, but the phrase "mine safety czar" has been applied to the position only since the appointment of
Richard Stickler to the post in 2006. Similarly, there has been a director of the
Office of Information and Regulatory Affairs since the office was created by the
Paperwork Reduction Act of 1980, but the term "regulatory czar" was not applied to the post until 2001. ==List of executive branch czars==