The, ongoing, collective, failure of Blacks, in America, to achieve economic equity, with Whites,  can be traced to certain characteristics that are inherent to that race.
First, it in a fact of life, that blacks, on average, have significantly, lower IQs than Whites. Then the problems associated with  low average IQ of Blacks, is compounded by their collective  tendency to drop out of school early, & to be disruptive to the learning environment, while in school.  Then add to this, the common use of foul language, & their manner of dress, with their pants down below their butts, & their tendency towards violent crime Blacks, by their behavior & poor attitudes, are the cause of their, generally low level of achievement in America. 

Thomas Jefferson, once said words to the effect, that, "While it is certain that the slaves would, one day, be free, it is equally certain that Blacks & Whites could not live together, under the same government."

Point being, that the races are not equal,