I think Thomas Sowell has previously noted that most of the income inequalities in the USA by racial group (e.g. White, Jewish, Asian, Hispanic, African-American) can be accounted for by their demographic profile.
Some very interesting stats above, they don't consider inheritance... which as noted by Steven Pinker complicates matters even further:
"Parental love causes the fundamental paradox of politics: no society can be simultaneously fair, free and equal. If it is fair, people who work harder will accumulate more. If it is free, people will give their wealth to their children. But then it cannot be equal, for some people will inherit wealth they did not earn. Ever since Plato called attention to these tradeoffs in 'The Republic', most political ideologies can be defined by the stance they take on which of these ideals should yield."