 M @-@ 188 is maintained by the Michigan Department of Transportation ( MDOT ) like other state highways in Michigan . As a part of these maintenance responsibilities , the department tracks the volume of traffic that uses the roadways under its jurisdiction . These volumes are expressed using a metric called annual average daily traffic , which is a statistical calculation of the average daily number of vehicles on a segment of roadway . MDOT 's surveys in 2010 showed that 986 vehicles in the city of Eaton Rapids , and 1 @,@ 103 used the trunkline outside of town , traveled along the highway on average . M @-@ 188 has not been listed on the National Highway System , a network of roads important to the country 's economy , defense , and mobility . 
