Assuming everyone who graduated with a CS degree from the US was hired at an equivalent then one would expect something closer to 7%-8%.
None of these things mean that negative racial discrimination or stereotyping don't exist, just that we shouldn't expect numbers for a particular industry population to match the aggregate stats on who graduated last year.
When I look at the data, I see that 2.5% of graduates are black. I'm looking at PhD, Master's or Bachelor's in CS in 2015.[1]
The totals exclude those with unknown ethnicity:
15 black CS PhDs out of 1442
110 black CS Master’s out of 8,923
425 black CS Bachelor’s out of 11,974
(15+110+425) / (1442+8923+11974) = ~0.0246
[1] 2015 Taulbee Survey, Computing Research Association
http://cra.org/wp-content/uploads/2016/05/2015-Taulbee-Surve...
EDIT: I believe one big source of the difference between our numbers is whether you count "Information" degrees as a CS degree. My number only looks at "Computer science" degrees, whereas your data looks at "Computer sciences" degrees.
2009 data:
(numbers are CS/All, CS% from all CS, CS% from all graduates in category)
Total graduating with a CS degree: 38,496/1,619,028(100%, ~2.37%)
Total White: 23,021/1,069,016(~60%, ~2.15%)
Total Black: 3,868/145,988(~10%, ~2.64%)
Total Asian/Pacific Islander: 2,894/105,246(7.5%, ~2.75%)
Total Hispanic: 2,999/137,746(7.80%, ~2.17%)
Interestingly, both Black and Asian/PI are significantly above the number of CS graduates per capita, and White/Hispanic are below.