See p60-191.pdf for a report including graph that income inequality has gone up since 1968. It is going up for reasons “still not entirely understood.”
“Although the Census Bureau has been measuring incomes for a half-century and a a large number of factors have been identified as contributing to changes in inequality, the root causes are still not entirely understood.”
The root cause is the 1965 Immigration Act, i.e. legal immigration is the root cause of the income inequality the census measures. The graph shows inequality went down during the period before the 1965 Immigration Act, the immigration restriction period. Inequality bottomed out around 1965 to 1968 and then went back up.
No immigration the graphs shows inequality going down, after legal immigration, income inequality goes up on the graph. The graph shows that just around 1965 and for a couple years, income inequality bottomed out. This is despite the passage in 1964 of the Civil Rights Act.
See Census gov p60-229.pdf page 14 of pdf for graph of men’s median wages which are lower than in 1973. After 1973, men’s wages flatlined. This supports identifying the 1965 Immigration Act and legal immigration as the cause.
Senators who voted for S. 2611, amnesty and the path to more income inequality.
||Kyl (R-AZ), Nay
||McCain (R-AZ), Ye
||Martinez (R-FL), Yea
||Nelson (D-FL), Yea
||Durbin (D-IL), Yea
||Obama (D-IL), Yea
||Bunning (R-KY), Nay
||McConnell (R-KY), Yea
||Santorum (R-PA), Nay
||Specter (R-PA), Yea
||Allen (R-VA), Nay
||Warner (R-VA), Yea