This graph almost needs no explanation.
From Modeled Behavior:
Here we can see that the Top 1% has more than triple its income with fairly steady growth since 1980. The middle and lower classes have seen only about a 15% increase in real income with all of those gains coming after the early 90s.
What’s even more interesting to me is that the gains to the Top 1% seem to be steady and at first glance trend reverting. That is, there appears to be a consistent underlying rate of growth ever since 1980, with income rising above trend during booms and falling below during recessions.