An insurance fund that slaps a fee on every Michigan car to pay for catastrophic injuries suffered in accidents has been ordered to open its books and demonstrate how it sets the annual rate. The decision by an Ingham County judge could shed more light on the Michigan Catastrophic Claims Association, which was created by the Legislature to reimburse insurance companies for claims that exceed $500,000. Michigan’s no-fault insurance law provides unlimited lifetime coverage for medical expenses tied to auto wrecks. Michigan drivers now pay $175 per car per year - a sum that’s up 67 percent since 2008 - on top of other charges by their insurer.