Mich. Comp. Laws § 211.43c

Sec. 43c. Notwithstanding section 43, if there is not an agreement for alternative schedules for delivering interest earned, the local tax collecting unit shall retain interest earned on the collections of the state education tax levied under the state education tax act, Act No. 331 of the Public Acts of 1993, being sections 211.901 to 211.906 of the Michigan Compiled Laws, while in the possession of the local tax collecting unit.