To start to understand why auto insurance costs so much more in Detroit than it does outside the city, it helps to start with some statistics. First:

Two-thirds of all cars stolen in the state of Michigan are stolen in Wayne County, which has not quite 20 percent of the state’s population.

“It’s astounding, those figures,” said Pete Kuhnmuench, director of the Insurance Institute of Michigan, an industry advocacy group.

Michigan also has the seventh-highest percentage of uninsured motorists. And there’s the simpler fact that, in urban settings, there are more drivers to run into, and more of those drivers are likely to be uninsured.

To Kuhnmuench, insurance is a dispassionate business, even as it arouses ire in those who have to buy it. Rates have to be actuarially justified, and are a matter of calculating risk, predicting how likely you are to need your insurer’s services.

“We don’t collect ethnic data,” he said. “When people accuse us of trying to take advantage of people, I have to laugh.”

Sen. Bert Johnson isn’t laughing. A resident of Highland Park, a small, poor city surrounded by Detroit, he pays $6,000 a year to insure his 2005 Jaguar. He sees insurance reform not only as a matter of justice for poorer people, but also thinks it would lift a barrier to voting for those burdened by high urban rates.

“I feel the turnout rates are low (because of this),” he said. “Detroiters have found a way to not be a part of the voting numbers, (because) they need lower insurance, or need to have their children in a better school.”

The Insurance Institute of Michigan reports the average Michigan auto-insurance customer pays $1,073.52. Kuhnmuench said his group does not calculate separate figures for individual urban areas, due to wide disparities between insurers' quotes and discounts. The state of Michigan also does not provide data on city-level averages.

Reform of Michigan’s no-fault auto insurance system was one of Gov. Rick Snyder’s policy priorities laid out in his State of the State address this January, and he signed an executive order creating a new state Department of Insurance and Financial Services the following day.

But no-fault reform is unlikely to offer particular help to Detroiters, whose problems are based in the city’s own.

But the biggest obstacle to relief may be assumptions, based on anecdote and word of mouth.

The state’s rate survey, based on 2008 data, is simultaneously both one of the state’s most popular documents, and one of its most inaccurate. Estimates of what different typical customers would pay for typical coverage may be correct for some companies, but not for others, because of different methodologies used in calculating rates, said Catherine J. Kirby, of the Michigan Office of Financial and Insurance Regulation.

Insurance quotes tend to start at one figure and fall to another, based on various applied discounts that vary from customer to customer, she said. The state is preparing a new buyer’s guide, to be released later this year, focusing “on how to shop and compare insurance coverages rather than providing rating examples.”

The new guide will be a worksheet, for customers to figure out all the factors that can be turned into discounts on auto insurance.

“One thing that guide does do is, it shows you that companies vary,” said Kirby. “It’s beneficial to shop around for insurance. It’s not something consumers like to do.”

But, she said, it’s worth it, having done it herself:

“I ended up saving almost $1,000.”

Staff Writer Nancy Nall Derringer has been a writer, editor and teacher in Metro Detroit for seven years, and was a co-founder and editor of GrossePointeToday.com, an early experiment in hyperlocal journalism. Before that, she worked for 20 years in Fort Wayne, Indiana, where she won numerous state and national awards for her work as a columnist for The News-Sentinel.