27% of Hispanics and American Indians reported experiencing racism.  23% of whites did.  That's only a 4% difference, which might even be within the realm of random error and statistically insignificant.  Whites are even more likely to report experiencing racism than Asians (18%).  

And that's based on self-reported feelings.  So if someone doesn't get the promotion, they may feel it was because of race, regardless of race.  It doesn't mean it was actually because of race.   Self-rationalization and attribution of disappointments to racism are probably inflating these numbers from the true reality.