Michigan Compiled Laws, Chapter 484. Telephone, Telegraph and Radio § 484.1412a

Sec. 412a. (1) Within 90 days after the first day of the calendar year following the year in which a service supplier commenced collection of the emergency telephone technical charge under section 401d,  1 and within 90 days after the first day of each calendar year thereafter, a service supplier collecting the emergency telephone technical charge for the purpose of providing 9-1-1 service pursuant to this act shall make an annual accounting to the 9-1-1 service district of the total emergency telephone charges collected during the immediately preceding calendar year.

(2) If an annual accounting made pursuant to subsection (1) discloses that the total emergency telephone technical charges collected during the immediately preceding calendar year exceeded the total cost of installing and providing 9-1-1 service within the 9-1-1 service district for the immediately preceding calendar year according to the rates and charges of the service supplier, the service supplier shall adjust the emergency telephone technical charge collected from service users in the 9-1-1 service district in an amount computed pursuant to this section. The amount of the adjustment shall be computed by dividing the excess by the number of exchange access facilities within the 9-1-1 service district as the district existed for the billing period immediately following the annual accounting. Costs of the service supplier associated with making the adjustment under this subsection as part of the billing and collection service shall be deducted from the amount to be adjusted.

(3) If the annual accounting discloses that the total emergency telephone technical charges collected during the calendar year are less than the total cost of installing and providing 9-1-1 service within the 9-1-1 service district for the immediately preceding calendar year according to the costs and rates of the service supplier, the service supplier shall collect an additional charge from service users in the 9-1-1 service district in an amount computed pursuant to this section. Subject to the limitations provided by section 401d, the amount of the additional charge shall be computed by dividing the amount by which the total cost exceeded the total emergency telephone technical charges collected during the immediately preceding calendar year by the number of exchange access facilities within the 9-1-1 service district as the district existed for the billing period immediately following the annual accounting.