A. For a judge or justice who occupied such an office prior to July 1, 1980, but who had ceased to hold such an office prior to that date and who elected to be excluded from the provisions of the Judicial Retirement Act; or a judge or justice who occupied such an office on July 1, 1980, but who elected to be covered under the provisions of the retirement plan in effect at that time, the amount of monthly pension is an amount equal to one-twelfth of:

seventy-five percent of salary received                         X                                 number of years of during last year in office prior to retirement service, not exceeding ten years, divided by ten.

B. For a judge or justice who initially became a member before July 1, 2005 and who initially occupied such an office after July 1, 1980; or a judge or justice who occupied such an office on or before July 1, 1980 and who has elected to be covered pursuant to the provisions of the Judicial Retirement Act, the amount of monthly pension is an amount equal to the sum of:

(1)     for service credit earned on or before June 30, 2014, an amount equal to one-twelfth of:

seventy-five percent of salary received during last year in office prior to retirement     X .05 X (number of years of service, not exceeding fifteen years, plus five years); and

(2)     for service credit earned on and after July 1, 2014, an amount equal to one-sixtieth of the greatest aggregate amount of salary received for sixty consecutive, but not necessarily continuous, months in office multiplied by the product of three and one-half percent times the number of years of service credit.

C. For a judge or justice who initially became a member after June 30, 2005 but on or before June 30, 2014, the amount of monthly pension is an amount equal to the sum of:

(1)     for service credit earned on or before June 30, 2014, an amount equal to one-twelfth of the salary received during the last year in office prior to retirement multiplied by the product of three and seventy-five hundredths percent times the sum of the number of years of service; and

(2)     for service credit earned on and after July 1, 2014, an amount equal to one-sixtieth of the greatest aggregate amount of salary received for sixty consecutive, but not necessarily continuous, months in office multiplied by the product of three and one-half percent times the number of years of service credit.

D. For a judge or justice who initially became a member on or after July 1, 2014, the amount of monthly pension under form of payment A is an amount equal to one-sixtieth of the greatest aggregate amount of salary received for sixty consecutive, but not necessarily continuous, months in office multiplied by the product of three and one- fourth percent times the number of years of service.

E. The amount of pension under form of payment A for a pension calculated pursuant to Subsection D of this section shall not exceed eighty-five percent of one- sixtieth of the greatest aggregate amount of salary received for sixty consecutive, but not necessarily continuous, months prior to the member leaving office.

F. The amount of pension payable for a pension calculated pursuant to Subsection A, B or C of this section shall not exceed eighty-five percent of one-sixtieth of the greatest aggregate amount of salary received for sixty consecutive, but not necessarily continuous, months prior to the member leaving office. A pension benefit determined pursuant to this subsection shall not be less than the benefit earned as of June 30, 2014.