Ms Josephine Feehily:

They are based on properties sold since 2010. We have the figures for 2010, 2011 and 2012 and we recently added the figures for the most recent sales. In addition, we have valuations available from other data sources. We have bought some values in cases in which there were gaps in the data and our existing data was not sufficiently representative. We have paid to fill in the gaps. We have a representative sample that will give average indicative values at the level of electoral area. of which there are approximately 3,500 areas. It will distinguish between houses that are detached, bungalow, semi-detached, rural, urban and before or after 2000.