How come black immigrants not being counted in the black population?

I found it odd that the census is not counted full blooded Afro Caribbean,Afro Latin and African into the black population is it me or it seem like the census want the black population to be smaller then what it really is. Number of cities in the us got a growing black immigrants population like DC,Dallas,Houston,Chicago,Detroit,Miami,… York,Atlanta and Oakland but they not being counted with the black population which I found it to be not fare at all. They show don't got no problem adding hispanic and other group into the white population.