I mean I am using my Context Clues to guess that this thread is US-based, but I can say that about 10-15 years ago in the UK there was a... newspaper? NGO think tank? God I can't remember now. But someone realised that the economic class system in the UK no longer actually represented UK society, and so tried to make another.
Because, of course, that's the thing that no one has mentioned in this thread - classes are social stratas based on wealth, but with culture bolted on. The concept of upper, middle and working class didn't exist for Ancient Rome, which had patricians, equatores, plebians, freedmen and slaves. There's crossover, sure, but their society was structured fundamentally differently enough that the class system we use wouldn't apply - and vice versa.
Anyway, they tried making a new one, and I remember that the majority of my friends fit into one of the new classes. I think the best way to fit it into the old system would be financially working class, culturally middle. Can't remember what they called it, but that was the issue - the fact is, wealth and culture are no longer linked in the way they used to be. So yeah, of course there's a lot of cognitive dissonance involved now when people try to talk about class - we're still using antiquated terms and slapping antiquated political morality onto them when the things they describe no longer exist. Of course no one knows where anyone fits in. No one fits in now.
Edit: just looked it up and found it! Sociologists from UK universities put it together, and the BBC hosted it; looks like you can still take the test and see yours