What is considered "middle class" on CC?

Its funny how different people’s view on middle class can be. Shopping at Walmart and driving cars until they die is something I thought middle class families do but for someone else that’s a horrible standard of living. I see the argument of COL but I don’t agree with the very first post that standard of living increases with more money, so they are still middle class. IMO having that standard of living increase just shows that you are not middle class anymore. I guess there is no real answer to this but its fascinating to see how people’s perceptions of “middle class” varies.