There's nothing new about the flawed/missing data, @Fetaface; reports have mentioned it for years, but interestingly it doesn't stop some picking whatever bits that suit to insist most group abusers are (insert identifier of choice)
It's true that the Home Office also claimed most such groups are white, but then like all governments they'll claim whatever's politically expedient regardless of the actual facts, knowing perfectly well that the media will do the rest
I would however like to know, given the proven reluctance of our authorities to address this at all, just what influences were brought to bear over that mere one third of cases where ethnicity was noted and whether there was encouragement to gatheer data on some races while leaving others unrecorded, but whether this will ever be focused on is anyone's guess