I have made this point before, but Tyler Cowen has a great chart from a new study. The explanation is here, but basically they have defined the bands based on some income break points corrected for family size and inflation over time.
A reader sent me a nice note with this link, saying that I had been right many years ago when I began making this point. That's good, but I will also confess to be wrong on a related point -- I said 8 years ago that the one good thing about having a Democratic President was that the media would become much more positive suddenly about the economy. On that, I was wrong. The media still has a strong bias towards telling everyone that their life is getting ever worse, even when no such thing is true.