See Part 1 here
It was probably not distressing to many of you money grubbing young capitalist monkeys at WSO (and I mean that as a complement) to hear on the evening news a few weeks ago that the share of aggregate real (inflation adjusted) after tax income going to the top 1% of American households had doubled between 1979 and 2007, reaching 23.5%.
Of course many people were highly distressed by this widely publicized statistic emanating from the CBO report issued upon request of liberal Senators Chuck Grassley and Max Baucus. But not you monkeys. You probably cheered. After all, most of you intend to be in that 1% someday,and are working hard to get there.
Therein lays a tale revealing the misleading, if not dishonest, character of
studies of the income quintile distribution, and/or changes in the distribution
of total income shares, or of average incomes in each quintile, over time.
They convey the misimpression that the people in each quintile are the
same people year after year, like serfs and lords with lifetime status settled
at birth in a medieval system.
Most of the public outrage generated by hearing about how much more
the top quintile families earn (or the top 5%, or 1%) in comparison to
the bottom quintile families, stems from that misimpression. That false
impression is seldom corrected by those who make or propagate such
studies. CBO didn't, and neither Grassley nor Baucus will.
Reality is quite different. The typical experience of a person born in the
U.S.A. is this: most are born to a family somewhere in the middle quintiles.
When we roll off that high-school assembly line, move out of our parent's
home, and either go to college or start dipping our toes in the job market,
we become relatively poor.
Quite frankly, with little knowledge, skill, or experience, we aren't worth
much to employers at first. Besides, we shift employments rather
frequently, looking for our 'niche'. Eventually, though, we find one. We
also get married and start building a family.
Over time we complete our formal education, get on-the-job training, gain
experience, skill at our jobs, and seniority, taking more responsibility. We
become more productive and valuable to our employers so our incomes
rise over time.
Typically, then, we start out relatively poor (after high school) and rise over
time through the income quintiles. Eventually we reach our peak earning
years, at income levels that, even after adjusting for inflation and taxation,
are large multiples of what we started with.
Later in our lives, of course, we retire and our income falls somewhat.
Most of us are comparatively asset rich, however, having paid off our
mortgage, accumulated an investment/retirement portfolio, a couple of
cars, a boat or motor home in the back yard, etc. Note that
none of this normal experience is reflected at all in a typical pure quintile income
How much harder would it be to spark outrage by people in the lower
quintiles, and gain support from them for raising marginal tax rates on
those in the higher quintiles, if they understood that they are quite likely to
end up in one of those higher quintiles paying those extortionate tax rates?
How much harder would it be to engender guilt on the part of people in the
upper quintiles, thereby suppressing their resistance to a raise in marginal
tax rates to fund income redistribution, if they knew that it is typical even of people in the bottom quintile families to end up much better off in life over
time (and that this is particularly likely when marginal tax rates are low)?
A few years back (see The Journal of Private Enterprise 14 no. 1, 1998)
an economist named Don Mathews showed just how devoid of real
information the quintile income distribution is. He designed an imaginary
economy in which everyone began work at age 21, got a 6% raise at the
end of each year, and retired at age 65. Each year a new cohort of 21
year-olds was added and one just turning 65 was deleted. The lifetime
incomes of all citizens were therefore identical.
At any point in time, however, each population cohort was at a different
stage in life, with a different income from the others. Mathews then ranked
everyone in this imaginary economy by income, divided them into quintiles,
and calculated the share of total income each quintile obtained. It was
5.4% for the poorest quintile, 9.1% for the second, 15.4% for the third, 26%
for the forth, and 44% for the richest quintile.
Amazingly, that quintile distribution was extremely similar to the actual
American quintile distribution at the time. Clearly a quintile distribution
study (such as the CBO study) providing no data on mobility of the actual
persons, families or households included in the study between the quintiles
reveals virtually nothing about inequality itself!
Of course in the real world lifetime incomes are not identical, the way they
were in Mathews' thought experiment. But there is a great deal of mobility
of persons through the quintiles. How much? Hang on for part 3.