If you are a justice of the Washington supreme court or a judge in the court of appeals, superior court, district court, or municipal court and are an eligible member of the public employees' retirement system Plans 1, 2, or 3, you may purchase an increase on the benefit multiplier on past judicial service credit earned before becoming a judicial benefit multiplier (JBM) program member. The cost formula for purchasing the increase is equal to five percent of your salary earned for each month of increase, plus five and one-half percent annual interest, accumulated monthly, or the actuarial cost, whichever is less. See WAC 415-108-350.
The actuarial formula to determine the cost to increase past judicial service to the higher benefit multiplier is:
Wash. Admin. Code § 415-02-385