Lots of pages show the data in various ways. The chart Fig 5 on page 7 is pretty clear for household income. Table 2 page 34 shows every quintile becoming riche

Lots of pages show the data in various ways. The chart Fig 5 on page 7 is pretty clear for household income. Table 2 page 34 shows every quintile becoming richer over time. Lots of the content also explains forces affecting this. There's plenty of such studies from the Fed and from CBO, among others.