Any interest that may be awarded on a back pay award made by the commission shall be added to the award and computed at the annual rate specified in s. 814.04(4), Stats., simple interest. Interest shall be computed by calendar quarter. Interest shall begin to accrue on the last day of each calendar quarter, or portion thereof, in the back pay period on the net amount of back pay attributable to that calendar quarter, or portion thereof, after any set-offs, and shall continue to accrue until the date of compliance with the back pay order.
Wis. Admin. Code Employment Relations Commission ERC 94.07