[Cogito]

I have no idea if this is related, but I remember reading something a while back about how hard this type of data is to interpret.

A poignant example was given, describing how an entire city might switch countries, for example from Ukraine to Russia (and maybe back again?), and how that is a difficult situation to deal with.

Do the entire occupants of that city count as emigrants? What if they then decide to move back across the border? What happens if the city moves back a year later?

In any case, I don't know if there are issue like that here, but I would not be surprised if there were.