Figures from the Federal Institute for Population Research (BiB) showed that Germany now has the second-oldest population in the world, after Japan.
But there are large regional differences across the Federal Republic.
In medium-sized cities with universities, such as Freiburg or Heidelberg, the average age was much lower, at just over 40 years.
But in rural areas of the former East Germany, where many young people moved away in the years after reunification in 1990, the average age is closer to 50 years.
The below map from the BiB shows average age in German districts - the reddest areas are youngest, while the oldest areas are darkest blue.
The persisting weak economy in the "new states" in the East that became a part of the Federal Republic 25 years ago hasn't encouraged those who left to return – or young people born since then to stay.
A report released earlier this year by the Bertelsmann Foundation warned that the East German population is set to plunge still further by 2030 - and the BiB agrees.
In parts of Thuringia, Brandenburg and Saxony-Anhalt, the BiB experts say almost half of the people there will be over 60 years old by 2035.
Meanwhile, the West boasted the areas with the lowest average ages.
Vechta, a town of 32,000 in Lower Saxony, is the youngest district in Germany, with an average age of 40.1 thanks to its high birth rate.
SEE ALSO: East German population to plunge by 2030