Figures like yours usually come from just comparing today's 10% to the 10% from earlier date, and just saying "new entrant" vs "existing entrant". But a new ent

Figures like yours usually come from just comparing today's 10% to the 10% from earlier date, and just saying "new entrant" vs "existing entrant". But a new entrant from the bottom 10% would be more interesting than a new entrant from the second 10%. You can get a more holistic view using, say, quintiles: (grabbed off Wikipedia) 42% of children born to parents in the bottom fifth of the income distribution ("quintile") remain in the bottom, while 39% born to parents in the top fifth remain at the top.[5] Only half of the generation studied exceeded their parents economic standing by moving up one or more quintiles.[5] Moving between quintiles is more frequent in the middle quintiles (2-4) than in the lowest and highest quintiles. Of those in one of the quintiles 2-4 in 1996, approximately 35% stayed in the same quintile; and approximately 22% went up one quintile or down one quintile (moves of more than one quintile are rarer). 39% of those who were born into the top quintile as children in 1968 are likely to stay there, and 23% end up in the fourth quintile.[5] Children previously from lower-income families had only a 1% chance of having an income that ranks in the top 5%.[7] On the other hand, the children of wealthy families have a 22% chance of reaching the top 5%.[7]