Ms Barbara Nolan:

For example, persons could apply to remain on the electoral roll. That would be already a sign that they are conscious that they are disappearing off the electoral roll and they want to remain on it. It could be something as straightforward as that which does not require any major demonstration or sets of criteria to fulfil before they could remain on the electoral roll. It could be the simple act, when they are leaving the country, of stating that they do not want to be taken off the electoral roll.