Michigan Compiled Laws, Chapter 141. Municipal Financing § 141.611

Sec. 11. Subject to the exclusions, adjustments, exemptions, and deductions herein provided, an annual tax of 1% on corporations and resident individuals and of 1/2 % on nonresident individuals for general revenue purposes and the purposes provided for in sections 11a and 11b  1 is hereby imposed as an excise on income earned and received on and after the effective date of this ordinance.However, if the governing body of the city adopts a resolution to impose the tax at a lower rate, the tax is hereby imposed at that lower rate. If the tax is imposed at a lower rate, the rate on nonresident individuals shall not exceed 1/2 of the rate on corporations and resident individuals.