<P> Once a judge meets age and service requirements he or she may retire and will then earn his or her final salary for the remainder of his or her life, plus cost of living increases . The "Rule of 80" is the commonly used shorthand for the age and service requirement for a judge to retire, or assume senior status, as set forth in Title 28 of the U.S. Code, section 371 (c). Beginning at age 65, a judge may retire at his or her current salary, or take senior status, after performing 15 years of active service as an Article III judge (65 + 15 = 80). A sliding scale of increasing age and decreasing service (66 + 14, 67 + 13, 68 + 12, 69 + 11) results in eligibility for retirement compensation at age 70 with a minimum of 10 years of service (70 + 10 = 80). </P> <P> Under section 376 a survivor's annuity to benefit the widow, widower or minor child of the judge may be purchased via a deduction of 2.2% to 3.5% from the retirement benefit . </P> <P> There are currently 870 authorized Article III judgeships: nine on the Supreme Court, 179 on the courts of appeals, 673 for the district courts and nine on the Court of International Trade . </P> <P> The total number of active federal judges is constantly in flux, for two reasons . First, judges retire or die, and a lapse of time occurs before new judges are appointed to fill those positions . Second, from time to time Congress will increase (or, less frequently, decrease) the number of federal judgeships in a particular judicial district, usually in response to shifting population numbers or a changing workload in that district . Although the number of Supreme Court justices has remained the same for well over a century, the number of court of appeals judges has more than doubled since 1950, and the number of district court judges has increased more than three-fold in that period . </P>

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