How much money you need to make to be ‘middle class’ in every big city

Exactly - in a well connected world/economy, local measurements of income don't mean much. As someone that's lived in and near Detroit, the incomes listed there have no relation to my idea of what's lower/middle/upper class. Most people in the area would probably peg those closer to what you see on Dallas or San Diego's charts. Detroit proper (as opposed to the sprawling Detroit area, which mostly looks like any suburban metro area) is simply a very poor city - I doubt it's much comfort to anyone making $30,000 there that they happen to fall in the middle, and I doubt that an employer would have any luck trying to pay an engineer a $60,000 "upper class" salary.

For me middle class (in america) would mean:

- Being able to buy a house with a yard an hour or less away from work.

- Being able to buy the amount of cars needed (1 to 2 cars on average).

- Being able to afford groceries/health insurance/school for everyone in the family.

But I know this is pretty random, it's just my idea of middle class.