I understood what you meant. But in the United states race is also a factor in class determination insomuch as a poor White person will still self identify and often be externally confirmed as being of a higher class than a Black person in the same income bracket. This is why, in many cases, affirmative action policies target non-whites in particular regardless of income. Black people, regardless of income, experience the impact of this social stratification on a daily basis. It affects their social mobility, income, and health outcomes.