Eoin Ó Broin (Dublin Mid West, Sinn Fein) | Oireachtas source

Is there any way for the CSO, perhaps as part of this exercise, to attempt to match or look at where two separate census forms were filled in for a single property to try to establish things? I appreciate that all of this is tricky. I do not mean it as a criticism in any way when I say that 47,000 "possible informal" arrangements seems potentially too large. It is worthy of interrogating more because it is a lot.

If we think of the types of people who do not need to be registered, whether it is licensees, people who rent a room, family members renting from family or people not paying rent, that is quite a large number. Let us assume, for example, that not everybody who is renting a room will have filled in the census form. They may not have been there on the night or whatever. Was there any way of looking at double census forms for a single property and whether the CSO was able to extrapolate the possible number of licensees from that? Let us say I had my census form at my principal private residence and Deputy O'Callaghan had his own census form at the same address, but also ticked the box that he was renting from a private landlord. Is the CSO able to make that kind of analysis of the data?