That's actually not quite as incorrect as we might intuit; we talk about the top 1% and earnings quintiles and such as though they're static fixtures, but mobil

That's actually not quite as incorrect as we might intuit; we talk about the top 1% and earnings quintiles and such as though they're static fixtures, but mobility in and out of those positions is actually pretty robust. https://www.nytimes.com/2014/04/20/opinion/sunday/from-rags-to-riches-to-rags.html?smid=pl-share https://www.nytimes.com/2014/04/20/opinion/sunday/from-rags-... TL;DR: > It turns out that 12% of the population will find themselves in the top 1% of the income distribution for at least one year. What’s more, 39% of Americans will spend a year in the top 5% of the income distribution, 56% will find themselves in the top 10%, and a whopping 73% will spend a year in the top 20% of the income distribution. The reverse side of that phenomenon applies, as well - a significant portion of the population will find themselves in the _bottom_ part of the distribution at some point in their lifetimes, as well.