Again, it's highly problematic defining mobility as "moving from bottom quintile to top quintile".
- Moving from bottom quintile to 2nd highest is significant mobility and completely ignored in this analysis.
- The analysis ignores the fact that the highest quintile in the US is higher in absolute terms than other countries. So moving from bottom to 4th may give more income than bottom to 5th in other countries.
- This analysis also ignores the changes of income within quintiles. The 3rd quintile in 1980 isn't the same income in 2020. 3rd quintile could see significant income improvements.
- This analysis also ignores government transfers.
- Countries that have a lower income spread, but overall less income would do better.
- Moving from bottom quintile to 2nd highest is significant mobility and completely ignored in this analysis.
- The analysis ignores the fact that the highest quintile in the US is higher in absolute terms than other countries. So moving from bottom to 4th may give more income than bottom to 5th in other countries.
- This analysis also ignores the changes of income within quintiles. The 3rd quintile in 1980 isn't the same income in 2020. 3rd quintile could see significant income improvements.
- This analysis also ignores government transfers.
- Countries that have a lower income spread, but overall less income would do better.