That is considerably more than in Germany’s neighbouring countries, the Czech Republic and France.
The figures from the German Office of National Statistics (Destatis) and Eurostat, which included 13,145 German households, showed 16.1 percent of Germans were at risk of falling into relative poverty, compared to 9.6 percent in the Czech Republic, 10.1 percent in the Netherlands and 14.1 percent in France.
It also suggested that relative poverty in Germany has been rising in spite of the robust economy and falling unemployment. Back in 2005, the number of people at risk of poverty was 12.2 percent. That figure had risen to 16.1 percent in 2011.
The study defined people earning less than 60 percent of the median income as at risk of poverty. By that measure a single person earning less than €980 a month and a family with two children on less than €2,058 a month were at risk of poverty in Germany.
Women were at more risk of falling upon hard times than men, particularly in the over-65 category. In the under 18 age group, 15.7 percent of females were at risk of poverty, compared to 14.8 percent of their male counterparts.
Just under a third of people living alone fell into the category too.
Merkel's Christian Democrats are under increasing pressure to bring in measures to combat poverty and in particular to address the growing problem of the so-called working poor.
Labour market reforms brought in by Merkel's Social Democrat predecessor, Gerhard Schröder, were successful in bringing down unemployment but have been criticized for supporting poor employers who hire cheap "mini-jobbers" instead of full-time staff.
Germany does not have a federal minimum wage. Instead, the government guarantees everyone a "living wage" by giving benefits to low-income workers.
The Social Democrats argue that this gives bad employers a competitive boost and has led to growing inequality. The party's call for a nationwide minimum wage of €8.50 an hour is likely to be a key demand in coalition negotiations.
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