The quintiles are not static. For example, when we were just starting out my wife and I were in the bottom 60%, but now we are in the top 40% and probably in the top 20%. People do not have to stay in the same quintile of earners over the course of their income-earning years, yet some do, many if not most as a result of the decisions they make regarding work and regarding consumption vs investment choices with the income they earn (or receive).
Exactly.
This is one of many facts that the America-bashers overlook when they're bad-mouthing the US economy --the Heritage Council did a nice study on income distribution lies here and it included a few other points, some of which they combined into this bar chart.
