Looks like there’s more data available on trends in income inequality. The Center on Budget and Policy Priorities presents a report titled “NEW CBO DATA SHOW INCOME INEQUALITY CONTINUES TO WIDEN: After-Tax-Income for Top 1 Percent Rose by $146,000 in 2004.” Their analysis is based on data from the Congressional Budget Office. They report:

The new CBO data document that income inequality continued to widen in 2004. The average after-tax income of the richest one percent of households rose from $722,000 in 2003 to $868,000 in 2004, after adjusting for inflation, a one-year increase of nearly $146,000, or 20 percent. This increase was the largest increase in 15 years, measured both in percentage terms and in real dollars.

In addition to other things, they also provide some graphs that show shifts in income distribution across the income spectrum.