what income bracket constitutes the poor, working poor, working class, etc.?

Are there official or universally accepted income brackets & descriptions for the poor, working poor, working class, middle class, professional class and upper class? I find alot of info on the working class or middle class, but no real description of what kinds of income makes you one or the other, or if it is not tied into income, but income vs. expendetures for your specific geographic region (80k a year will go much farther for buying land & houses in arkansas than in NYC, so is someone who makes 80k a year in NYC middle class, but professional class in arkansas?)

Here is something to start with.