Mich. Comp. Laws § 17.54: Past due payment.

Sec. 4.

Except as provided in section 5, if a payment owed by a principal executive department to a private enterprise for goods or services is past due, the principal executive department shall pay an additional amount equal to 0.75% of the payment to the private enterprise to which payment is due. The principal executive department shall pay an additional amount equal to 0.75% of the payment due for the first month and each succeeding month or portion of a month the payment remains past due.

A principal executive department shall not require a private enterprise to submit a petition, bill, statement, or other additional notice in order to collect an amount due under subsection (1).