You can see that a vast majority of blacks rarely or never experience the various forms of mistreatment. I thought racism was like a thick cloud that leaves no one untouched. If this were true, all blacks would give the same answer: "often" or at least "sometimes."
This looks like a case of some blacks interpreting everything in terms of racism, while others do not. You can see how supposed racist incidents are inherently ambiguous. Did the guy call you an idiot because you're black or because he thinks you're dumb? Notice how the interviewers did not ask, "How often are you called a racial slur?" This is an unambiguous incident, but it wasn't asked because it rarely happens. Researchers like to help blacks "find" racism.
In a later post, I'll look to see if we can use a person's characteristics to predict their perceiving racism. For example, I expect that suspiciousness will predict it.