Robert Frank details it:
The three decades after [WWII] saw incomes grow at an almost uniform 3 percent annual rate for families up and down the income ladder. Since the early 1970s, however, virtually all income gains have accrued to those whose incomes were highest to begin with. It’s a striking fractal pattern. Most of the gains have gone to the top 20 percent of earners, but the lion’s share of the gains within that group have gone to the top 5 percent. And within the top 5 percent, most of the gains have gone to the top 1 percent, and so on.
He follows up with a proposal for a progressive consumption tax.
(Video: A global view from a new OECD report, "Divided We Stand".)
The Dish 