Almost half of Michigan’s major roads are in poor or mediocre condition. That’s according to a new report from a national transportation research group called TRIP.

TRIP says driving on rough roads costs the average Michigan driver between $500 to $800 dollars a year per vehicle.

That’s due to factors like faster vehicle depreciation, additional repair costs, and tire wear.

According to the report, the condition of Michigan’s transportation system is “critical to the health of the state’s economy.”

The report also says one trillion dollars a year in goods are shipped to, from, and within sites in Michigan, and that those shipments rely heavily on the state’s roads and bridges.

TRIP says poorly maintained roads could mean businesses will relocate to areas with more efficient and more modern transportation systems.