Mich. Comp. Laws § 207.373

Sec. 3. There is levied upon and shall be collected from a person engaged in the business of providing an airport parking facility an excise tax. Through December 31, 2002, the rate of the excise tax is 30% of the amount of the charge for the transaction. Beginning January 1, 2003, the rate of the excise tax is 27% of the amount of the charge for the transaction.