The Judicial Conference calculates weighted caseload for each district by adjusting raw litigation data for case complexity, then dividing that by the number of authorized judgeships allocated to the district. But that statistic doesn't account for vacancies, many of which have lingered for years thanks to partisan gridlock in Congress. In 20 of the districts recommended for additional judgeships, judges have retired, died or been promoted, leaving seats empty.
Eight of the districts on the conference's list are home to so-called temporary judgeships, positions with an expiration date. Once a temporary judgeship expires, the next judicial vacancy in that district isn't filled. Last week, the conference recommended that Congress make all but two of the nation's 10 temporary judgeships permanent positions (signified as T→P below).
Permanent judgeships were last added to the bench 16 years ago, and many of the needy districts identified by the Judicial Conference haven't seen their benches bolstered in decades (the dates provided below reflect the creation of permanent judgeships, not temporary positions).