"That tells us one of two things. Either she’s moved and isn’t registered at her new address, or she’s where she used to be and census data is incomplete, which is more than likely down in the East End. Over a million and a half Londoners do not appear on any official lists, and that doesn’t even count the Undercity. There are plenty of places where census officials wouldn’t go even if toting a vanload of SAS laser packs at their backs. Most places with a Metropolitan Police security rating of C or worse have very incomplete data. And we’re heading into a C zone or lower, no question.