From Rags to Riches to Rags
How upwardly mobile are Americans? Let's look at the data:
It turns out that 12 percent of the population will find themselves in the top 1 percent of the income distribution for at least one year. What’s more, 39 percent of Americans will spend a year in the top 5 percent of the income distribution, 56 percent will find themselves in the top 10 percent, and a whopping 73 percent will spend a year in the top 20 percent of the income distribution.
Graph is from the American Enterprise Institute
The data shows significant upward and downward mobility in the US. People make fortunes and then lose them. Furthermore, this data shatters the myth that the rich stay rich and the poor stay poor. The top 1% and the bottom 20% are the same people, just at different stages of life. You could be a waiter and be in the bottom quintile of income when you're 22, but be a doctor and in a top quintile of income when you're 42.