10 years is a pretty big time range, and so you’d expect to see generational effects to show up. (i.e. people fall off the list, because they’re dead.) But this

10 years is a pretty big time range, and so you’d expect to see generational effects to show up. (i.e. people fall off the list, because they’re dead.) But this does highlight two important points: intergenerational and intragenerational mobility. https://en.wikipedia.org/wiki/Socioeconomic_mobility_in_the_United_States https://en.wikipedia.org/wiki/Socioeconomic_mobility_in_the_... WRT intergenerational mobility, the US does quite poorly when compared to other modern economies, with a very strong correlation between parental wealth and the child’s wealth. For instance 42% born into the bottom quintile, stay there in the United States, but only 25% remained in Denmark. 8% rose to the top in US, but again, 14% did in Denmark. Intragenerational mobility in my opinion is a bit of a red herring. Often you’ll hear someone trumpet some number about people moving from one group to another in a single year, but you have to look closer to the reasons why. Some people are just on the cusp of the cutoffs and so will bounce around it. Others are experiencing temporary outlays, and will very quickly return to their original levels. Unless the person’s move has some stickiness, along with some large absolute change, it’s meaningless noise.