I found detail on household incomes for each fifth at the Census.
H1 table - Income Limits for Each Fifth and Top 5 Percent of Households
Here's what it looks like from 2000 to 2012 :
Thats not too bad looking but now lets look at it in real dollars:
That doesn't look so good. Incomes are down from 2000 in real dollars in every fifth as well as the top 5%.
Its hard to see detail on the bottom 3 fifth groups given the scale so I'll show those groups separately:
There you can see more clearly the drop of real incomes for the bottom 60% of people.
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