Ms Deirdre Cullen:

I thank the members for their complimentary comments about the census. It is always nice to be acknowledged for one's work.

Mr. Dalton covered Deputy Ó Broin's question on the two different figures for new builds. Householders self-report and the Department has acknowledged that its figure of 50,000 is not necessarily for new builds. There is a reconnection component which means we are not comparing like with like. We have had to explain the increase of 8,000 in stock. It is a net increase and there is always obsolescence in the housing market. I am surrounded by many pages of numbers, which is testimony to the amount of data we produce. The 2011 census showed 150,000 dwellings built prior to 1911 but now it is 141,000, so 9,000 are missing from that year-build category alone. Our enumerators see an old cottage with a new bungalow down by the gate and make a determination as to whether it is habitable. As time goes on, some come out of the housing stock.

There are explanatory notes at the back of the forms relating to the HAP and RAS schemes. People are given instructions for cases where their landlord is private but people do not always read instructions. The definition of overcrowding which we use is a UN, internationally recognised one that looks at whether there are more persons than rooms. We will have a look at the section 23 definition again and, perhaps, do another little bit of work on that.

On the churn in vacant properties, we looked at dwellings which were vacant in 2011 but occupied this time around. There were originally 105,000 and 65,000 were vacant five years later. We produced a thematic map, which is on the website and where one can click on the different areas. One can see the darker colours on the eastern seaboard - they indicate where the churn is. Tomorrow, data will come out on how many of the 183,000 vacant dwellings were occupied five years ago. We have also looked at the household composition of those dwellings, the age of the householder, the year they were built and a whole range of things.

Details at small-area level on the 30,000 properties converted to flats will be available tomorrow. We need more data to be able to understand it. The population increased by 3.8% but the urban population increased by 4.9%, with the rural population increasing by 2%. Large towns with 10,000 or more people increased by 6.6%. Cork city grew at a faster rate than Cork county and Galway city grew at a faster rate than Galway county. Two very large tables will come out tomorrow which show the population of every town and village in Ireland between 2011 and 2016. They will also show the urban-rural divide and the population by area, which is one of our most important outputs. This will be the second of our thematic releases and it relates to population distribution and movements.

We were asked about our engagement with the Housing Agency. The topic of housing and the importance of data have landed on the public agenda in the past year. We reached out to the Department and have engaged with the Housing Agency, whose members have been out with us. Tomorrow, we will put out the results of our engagement with the agency and we will see how we can best serve their needs, without handing record data to them, which we are forbidden to do. The engagement has been more intense over the past six to nine months and that is normal as the topic has become more important. We do not cross-check any of the census data with administrative data except at a very aggregate and high level. We do not cross-check with the ESB or utility connections. We publish the data people give us - we do not second-guess whether somebody is divorced, whether they are Roman Catholic, etc. We observe, capture and report data.