Mich. Comp. Laws § 500.6434

Sec. 6434. Every domestic insurer subject to this chapter shall maintain a contingency reserve at all times at least equal to 1/10 of the total premium income for the preceding calendar year but not less than $5,000.00 for each kind of insurance enumerated in section 6406 which the insurer undertakes to issue and shall maintain a deposit with the state treasurer, of the kind and amount and for the purposes specified in section 411.