Mich. Comp. Laws § 213.65: Interest on judgment amount.

Sec. 15.

The court shall award interest on the judgment amount or part of the amount from the date of the filing of the complaint to the date that payment of the amount or part of the amount is tendered. However, if a portion of the judgment is attributable to damages incurred after the date of surrender of possession, the court shall award interest on that portion of the judgment from the date the damage is incurred.

Interest shall be computed at the interest rate applicable to a federal income tax deficiency or penalty. However, an owner remaining in possession after the date that the complaint is filed waives the interest for the period of the possession.

If it is determined that a de facto acquisition occurred at a date earlier than the date of filing the complaint, interest awarded under this section shall be calculated from the earlier date.