As of January 2008, Statistics Netherlands and the Dutch Land Registry office (Kadaster) jointly publish the House Price Index for existing own homes with reference year 2005=100. In order to maintain close correspondence between the index series and the present-day situation, the reference year is updated every five years. At the start of 2013, the reference year of the House Price Index for existing own homes will be changed to 2010 (2010=100).
Besides a change in the reference year, the method used to determine the internal weights of the index will also be adapted. For the 2005=100 series, the weights represent relative shares of dwelling transactions in a recent year. Starting from 21 February 2013, the weights will represent relative shares of the total stock of dwellings. Therefore, the House Price Index for existing own homes tracks the price change of the stock of dwellings rather than that of dwellings sold. Analyses show that the new approach has minimal effect on the level and mutations of the index.
Due to a drop in the number of dwelling transactions in recent years, the currently published index series have been re-evaluated. It was determined that the error margins of indices with a low number of transactions can be large. If the number of transactions continues to fall, the error margins might grow too large. For this reason, the level of detail of the series will be reduced. Starting from 21 February 2013 the following series will remain:
• The Netherlands (total); monthly, quarterly and annually
• The four groups of provinces; quarterly and annually
• The twelve provinces; quarterly and annually
• The six types of dwellings; quarterly and annually
• The four largest municipalities quarterly and annually
Besides the price indices, also the number of transactions, the mean price of dwellings sold, as well as the total value of all sold dwellings are published. Starting 21 February, 2013, these figures will be published in three separate tables. The two current tables will be discontinued.
Currently, Statistics Netherlands is investigating the possibility of publishing the annual series with a higher level of detail.