Mich. Comp. Laws § 38.842

Sec. 2. A local unit of government, for the purpose of computing retirement benefits of an employee who is a judge, shall use a figure which is the difference between the figure otherwise used under the local unit's retirement plan to compute retirement benefits, and those portions, if any, of the state salary standardization payment which are converted as an addition to the judge's state base salary for the purpose of computation of retirement benefits pursuant to sections 14a and 14c of Act No. 198 of the Public Acts of 1951, being sections 38.814a and 38.814c of the Michigan Compiled Laws.