You are right. That paper does not show any difference wrt time. My bad. Actually another paper from the same author shows that social mobility has not changed.
> 3. Rates of relative intergenerational mobility in the U.S. appear to have been flat for decades
> 4. It is a different story, however, for absolute mobility – which indicates how well a person does compared to their parents in absolute terms, rather than relative ones. On this measure of mobility, the last few decades have seen a sharp decline.
So I guess a better way to put it would be to say that because of rising costs in healthcare and housing etc, the social ladder has become more slippery; an accident or a medical emergency has a much bigger chance to push you down the social ladder that from earlier years.
https://www.nber.org/system/files/working_papers/w19844/w198...
This website summarizes a couple of key points from other papers from that author:
https://www.brookings.edu/blog/social-mobility-memos/2018/01...
> 3. Rates of relative intergenerational mobility in the U.S. appear to have been flat for decades
> 4. It is a different story, however, for absolute mobility – which indicates how well a person does compared to their parents in absolute terms, rather than relative ones. On this measure of mobility, the last few decades have seen a sharp decline.
So I guess a better way to put it would be to say that because of rising costs in healthcare and housing etc, the social ladder has become more slippery; an accident or a medical emergency has a much bigger chance to push you down the social ladder that from earlier years.