The difference between the median and the mean figures for income ($43,200 as compared to $70,700) reflects the concentration of income in the hands of the top income-earners. If the distribution of income above the median were similar to the distribution below the median (as in a normal or bell curve), then one would expect the mean and median calculations to be roughly equal. However, while the median figure indicates that half of US families have a before-tax income of less than $43,200, the large earnings by a relatively small section at the very top are enough to pull up the mean substantially.
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Even with this decline, the top bracket still earns substantially more now than it did in 1998, while the same cannot be said for those at the bottom income levels. The bottom 20 percent of the population saw their mean income go from $8,200 in 1995, to $9,200 in 1998, to $10,700 in 2001, up to only $10,800 by 2004.
The stagnation of incomes for most Americans comes with a decline in real wages. The report notes that the absence of any income growth is largely due to a decline in median wages of 6.2 percent from 2001 to 2004. The Economic Policy Institute recently reported that between 2003 and 2005, only wage earners in the 95th percentile and higher saw any gains in real pay. If family income has not declined in the same way as real wages, this is due to an increase in hours worked to counterbalance falling pay.
The income figures by themselves, however, do not adequately measure the real dynamics of the past period. A closer look at the data on family net worth, which measures total assets against total liabilities, is more revealing. Net worth is in many ways a more accurate measure of the financial stability of US families, since it takes into account such things as debt burdens and increased expenditures.
Here we find a much different story. The median family net worth for the entire population rose by only 1.5 percent from 2001 to 2004. This small rise, however, itself masks the different experiences of the rich and poor. The median net worth, measured in 2004 dollars for families in the lowest quintile by income (the 20 percent of US families with the lowest income), went from $7,400 in 1995, to $6,800 in 1998, to $8,400 in 2001, to $7,500 in 2004. Families in the second quintile saw median net worth go from $41,300, to $38,400, to $39,600, to $34,300.
That is, median family net worth generally stagnated or declined for the bottom 40 percent of the population throughout the period. The drop in the second quintile in particular is astonishing—over 17 percent from 1995 to 2004, and over 13 percent from 2001 to 2004.
For a substantial section of the population, median net worth is negative; that is, their debts outweigh their assets. The mean net worth for the bottom 25 percent of the population as measured by net worth (rather than income, as in the figures above) in 2004 was -$1,400, down from $0 in 2001, and closer to the figure of -$2,100 in 1998.
On the other hand, median family net worth for the top 10 percent rose steadily throughout the period, from $436,900 in 1995, to $524,400 in 1998, to $887,900 in 2001, to $924,100 in 2004. The mean net worth for this group was substantially higher, rising from $1.3 million in 1995, to $1.8 million in 1998, to $2.4 million in 2001, to $2.5 million in 2004. For both mean and median figures, the top 10 percent of US families saw a growth of over 100 percent in family net worth since 1995.
Here we have an interesting disjuncture. Both median and mean net worth for the top 10 percent of the population rose from 2001 to 2004, while mean pre-tax income fell. In other words, the richest 10 percent are earning less income on average, but their overall wealth is actually increasing. What explains this dynamic? It is, at least in part, a consequence of the sharp cut in taxes for the very wealthy, legislated in 2001. In spite of a decline in
pre-tax income for some sections of the rich, they were able to increase their wealth because they took more of their income home than ever before.
The Federal Reserve report does not give after-tax income figures in this report. However, Internal Revenue Service data from last year showed that after-tax incomes for the top 1 percent of the population rose 8.5 percent from 2002 to 2003, while the after-tax income for the bottom 50 percent declined by 1.1 percent over the same period.
http://wsws.org/articles/2006/mar2006/ineq-m02.shtml