How many people actually have Covid-19? https://www.mpg.de/14909105/0605-defo-137749-how-many-people-actually-have-covid-19
The demographic scaling model developed by researchers at the Max Planck Institute for Demographic Research in Rostock and University of Helsinki makes it possible to estimate the actual number of Covid-19-infections in different countries with just a minimum of data. According to this model, the number of cases in Germany is only 1.8 times higher than the number of confirmed cases. For Italy, however, the researchers estimate that the number of infected is 6 times higher than the number of confirmed cases reported by the health authorities.
Corona Social Sciences Shift in deaths from the very old to people in middle age Wind