[Regional life expectancy rankings : Methodological artefacts in population updates]. / Rangfolgen der Lebenserwartung auf Kreisebene : Methodische Artefakte durch Bevölkerungsfortschreibungen.

For the calculation of life expectancy on a regional level, data from the mortality statistics and population numbers are needed. The latter are derived from population censuses, which have to be undertaken every 10 years according to the EU regulation No. 763/2008. In Germany, the last census took place in 2011 (Census 2011). The current population numbers are calculated on the basis of the most recent population census (population update). Births, deaths, immigration and migration, in addition to other data, are taken into account in this calculation. However, with passing time since the last census, inaccuracies in population updates may increase, which can affect the value of life expectancy calculations.Based on the comparison of life expectancy rankings, the impact and extent of changing over from the 1987 to the more recent 2011 census for regional comparisons were examined in two parts of Germany, Bavaria and North Rhine-Westphalia. As expected, the results show that larger changes in the calculated life expectancy result from larger changes in population statistics. However, noteworthy changes in life expectancy rankings do not necessarily follow larger changes in the population numbers. Regional life expectancy rankings are potentially always influenced by inaccuracies in the underlying population statistics. This should be taken into account when interpreting such small-scale differences.