Here is what I found on Wikipedia:
"White Americans are the racial majority, with a 77.7% share of the U.S. population. Hispanic and Latino Americans amount to 17.1% of the population, making up the largest minority. African Americans are the largest racial minority, amounting to 13.2% of the population."
So, African-americans are 13.2% of the population.
Roughly 39% that go to college, graduate (and this is out of the percentage that actually go in the first place). So it makes sense that Tech companies, no matter how racially diverse, are hiring less African-Americans. Even if 100% went to college, they would still be only a fraction of the workforce, if completely represented.
We need to get to the root of the problem instead of focus on the symptoms. Symptoms have been focused on for many years (affirmative action, etc) and it doesn't seem to be working. What needs to happen is in the home and I don't think the government can really do anything about it.
72% of African-american children are born out of wedlock.
"Estimates for the percentage of African-American children growing up in single-parent households are slightly lower, at 67 percent"