Stunning numbers on have and have-not divide

They come from the new book by Jacob Hacker and Paul Pierson, "Winner-Take-All Politics," that lays out the income disparities between the nation's very richest and everyone else. Yes, I know you know there are disparities, but just consider average annual income between 1979 and 2006:

Poorest fifth: +11%
Second fifth: +18%
Middle fifth: +21%
Fourth fifth: +32%
80th-99th Percentile: +55%
Top 1 percent: 256%

From the book:

These mind-boggling differences have no precedent in the forty years of shared prosperity that marked the U.S. economy before the late 1970s. Nor do they have any real parallel elsewhere in the advanced industrial world.