A house price index based on the SPAR method

Within the European Union there has been a push to provide European governments and the European Central Bank with the statistics they need for monitoring the owner-occupied sector. This paper reports on the results of a project to develop a house price index for the Netherlands. From January 2008, Kadaster, the Dutch land registry office, and Statistics Netherlands began jointly publishing house price index numbers for the whole country and for some specific dwelling types and regions. A number of special institutional features of the situation in the Netherlands contributed to the choice of index construction method. The indexes are computed using the Sale Price Appraisal Ratio (SPAR) method, which utilizes the ratios of transaction prices and previous appraisal values. We describe the SPAR method, compare it with repeat sales methods and assess the reliability of the official Dutch appraisal values. Empirical results for January 1995-March 2009 are presented. The SPAR method performs well compared to repeat sales, and the results reported will be of interest to other countries that have, or could instigate, institutional arrangements similar to those in the Netherlands.