Steven Matthews (Wicklow, Green Party) | Oireachtas source

It is a really difficult task to try to identify all of this because the CSO is dependent on somebody voluntarily filling out the CSO form. Many people comply with that and are quite happy to do so. That is one aspect to collecting the data. The other aspect then is to register with the RTB, which is obviously a legal requirement for the landlord. We know some landlords do not do that, however. I do not envy the task the CSO has in this regard. It will never capture in its entirety every single dwelling arrangement in the country. Is there best practice? Does the CSO look at how other countries do registration where they have an RTB equivalent or data collection equivalent to the CSO? Do they say that if you got it down to in or around 10%, you would be doing well? Is there any international comparison on that?