The problem with statistics like this is that you dont know what exactly the area is. Berlin is HUGE, so there are lots of flats on the market which are feasible. You might be able to find a flat in Kleinmachnow, Spandau or Wilhelmshagen for cheap, but if you are studying or working in Berlin you usually search in the city center and rents there are waaaay higher than 13€/m².
Its the average for Q1 23: [https://de.statista.com/statistik/daten/studie/535119/umfrage/mietpreise-auf-dem-wohnungsmarkt-in-berlin/](statisa 2023)
The problem with statistics like this is that you dont know what exactly the area is. Berlin is HUGE, so there are lots of flats on the market which are feasible. You might be able to find a flat in Kleinmachnow, Spandau or Wilhelmshagen for cheap, but if you are studying or working in Berlin you usually search in the city center and rents there are waaaay higher than 13€/m².