Definition: Fixity

Category: Purchasing power parities

"When results are calculated originally for a group of Member States (countries) and then later the results are calculated for a wider group of Member States (countries), the PPPs (Purchasing power parities) between the original group of Member States (countries) shall nevertheless be preserved." Article 4(q) PPP Regulation.

The convention whereby the relativities between a group of countries that were established in a comparison covering just that group of countries remain unchanged, or fixed, when the countries of the group are included in comparisons with a wider group of countries. For example, the relativities for EU Member States established by Eurostat remain unchanged when the EU Member States are included in a comparison covering OECD Member Countries. If fixity was not observed, there would be two sets of relativities for EU Member States. The two sets would not necessarily be in agreement because the relatives and ranking countries can change as the composition of the group of countries being compared changes. Fixity ensures that Eurostat, the OECD and participating countries have only one set of results to explain to users. http://ec.europa.eu/eurostat/product?code=KS-RA-12-023&mode=view Eurostat and Organization for Economic Cooperation and Development (OECD), "Eurostat - OECD Methodological manual on purchasing power parities (2005 Edition)", Methods and Nomenclatures, Office for Official Publications of the European Communities, Luxembourg, 2006European Union, Regulation (EC) No 1445/2007 establishing rules for the provision of basic information on PPPs, Official Journal of the European Union No L 336, 20.12.2007, p. 1 - 24