A frequently cited result derived from the SOEP suggests that the poorest two quintiles of the population had hardly experienced any real income growth since reunification, and in addition, they did not benefit from the recent positive economic development in Germany. However, the real rise of only 1 per cent turns into growth of nearly 8 per cent over the last 20 years if the start of the investigated period is shifted slightly and if the influence of the newly added migration sample in 2013 is adjusted for. Likewise, the previously observed minus 8.5 per cent real income loss of the poorest ten percent shifts to a real gain of 5.7 percent since 1994. Furthermore, in relative terms the lower income groups have gained as much of the positive economic development of the past decade as the middle and upper income groups. Similar adjustments for the newly added samples of specific family types suggest that these estimates are rather lower bounds of real income growth in recent years.
Judith Niehues, 2017, Einkommensentwicklung, Ungleichheit und Armut – Ergebnisse unterschiedlicher Datensätze, in: IW-Trends 3/2017