Here's a short excerpt from a recent column by Paul Krugman:
Working families have seen little if any progress over the past 30 years. Adjusted for inflation, the income of the median family doubled between 1947 and 1973. But it rose only 22 percent from 1973 to 2003, and much of that gain was the result of wives' entering the paid labor force or working longer hours, not rising wages.Meanwhile, economic security is a thing of the past: year-to-year fluctuations in the incomes of working families are far larger than they were a generation ago. All it takes is a bit of bad luck in employment or health to plunge a family that seems solidly middle-class into poverty.
But the wealthy have done very well indeed. Since 1973 the average income of the top 1 percent of Americans has doubled, and the income of the top 0.1 percent has tripled.
Some of Krugman's critics, I've noticed, tend to forget that he has been writing about income inequality for a long time, that is, long before he became a columnist for The New York Times. I recommend his book The Age of Diminished Expectations, if only to read for yourself what he was writing in the 1990s.
Also, you might want to read Krugman's essay in conjunction with this column by Jonathan Chait.