I don't really know how the different economic classes are defined. It seems like everyone who isn't either wealthy or homeless likes to believe that they're middle or upper-middle class. I'd argue that if you can't afford a home, you're low or lower-middle class.
This is not meant to be a judgement against people who can't afford homes. If anything, I'm just pointing out the horrible income inequality and how the "vanishing middle class" has indeed vanished, to a large extent.