People are warned not to put much trust into the ethnicity estimates, sometimes even by the services themselves. Telling western Europeans apart is hard. It's

People are warned not to put much trust into the ethnicity estimates, sometimes even by the services themselves. Telling western Europeans apart is hard. It's either matching to specific people in the service's reference group who have declared that they are Scottish, or it's trying to guess based on the mix of ancestral populations 2000+ years ago ("western hunter gatherer", "early Neolithic farmer" etc.)