Detroit just filed for bankruptcy. Hereâ€s how it got there.

— Since 2000, Detroitâ€s population has declined 26 percent. There are now just 706,000 people in the city, way down from 1.85 million during its industrial heyday in 1950.

— The official unemployment is now 18.6 percent, and fewer than half of the cityâ€s residents over the age of 16 are working. Per capita income is an extremely low $15,261 a year, which means thereâ€s not all that much tax revenue pouring in.

— Low tax revenue, in turn, means that city services are suffering. Detroit has the highest crime rate of any major city, and fewer than 10 percent of crimes get solved. The average response time for an emergency call is 58 minutes. Some 78,000 buildings are abandoned or blighted and there are an estimated 12,000 fires every year. About 40 percent of the cityâ€s streetlights donâ€t work.

— High crime and blight are driving even more residents out of the city. Itâ€s also driving down property values, which means many residents have stopped paying property taxes. The city collected about 68 percent of the property taxes owed in 2011. Both of those things put a further strain on Detroitâ€s finances.

Another Washington Post piece — Detroitâ€s demise was decades in the making by Keith B. Richburg — takes a more personal approach to the story and does a nuanced job of handling the city’s racialized politics. From that piece:

Writers often speak of Detroitâ€s “glory days” as the 1940s and â€50s, when the city came to symbolize Americaâ€s manufacturing prowess and Detroitâ€s population peaked at nearly 2 million people, making it the fourth-largest city in the United States behind only New York, Chicago and Los Angeles. But it was also a deeply divided city, with Southern white and Southern black transplants in an uneasy, combustible mix.

There were race riots in the â€40s, when whites didnâ€t want to work on assembly lines next to blacks. And new black residents were “redlined” into certain neighborhoods. The police force was all white and like an occupying army in black neighborhoods. My father would always point out to me the restaurants along Grand River Avenue or Woodward that would not serve blacks when he arrived in the city.

Of course the city did explode, in riots in 1967, and that was when Detroitâ€s downfall — its current path to insolvency — was set in agonizing slow motion. The white families in my neighborhood, my friends, all fled to the safety of the suburbs. My street, and my neighborhood, went from mixed to all black in an instant. Many of the black newcomers who came couldnâ€t get mortgages, so most ended up as renters, not homeowners.

And etc. A demographic spiral like that has affected many American cities — and many, many neighborhoods within American cities — but it would be hard to find anything comparable to what has happened in Detroit.

I’m going to assume that Detroit’s demographic history at Wikipedia is correct (if it weren’t, someone would almost certainly have fixed it). It tells several amazing stories that aren’t fully detailed in either piece. A few notes:

• For decades, Detroit had a very large foreign-born population, a fact which likely contributed to some of the demographic tensions. In 1870, the foreign born population was 47 percent. It fell from that number, but it was still 40 percent in 1890, and even 26 percent in 1930.
• According to census data, the city’s population peaked at 1.85 million in 1950 and fell by more than half to 714 thousand in 2010.
• The white population of the city was close to 100 percent at the beginning of the 20th century and was still 91 percent in 1940. The non-Hispanic white population is now below 8 percent.
• While the number of whites in the city has been declining sharply, so too has the black population, which peaked in 1990 at 778 thousand. In that census, blacks comprised 76 percent of the population. On a percentage basis, the black population has continued to grow, but the 2010 census counted only 590,000 blacks in the city.
• From 2000 to 2010, the city lost 44,000 non-Hispanic whites and lost 185,000 blacks, while adding about 1,500 Hispanics.

Given ordinary birth and death rates, these losses are even more extraordinary.

Clearly, the newfound middle-class mobility of the mid-20th century — especially for an American city synonymous with the automobile culture — played a role in this collapse. I’d love to see more on those trends and on the money spent to expand roads in suburban areas.

Richburg notes Mayor Dave Bing’s ideas regarding shrinking the city (you can read a brief piece here), but that’s a long, complex endeavor that will be resisted by many residents. And merely shrinking the city will not solve the problems of pension obligations and other debts.

All told, I think it would still be a really exciting time to be in Detroit. If it weren’t so cold.