In 1949, Geiger did an empirical study of social stratification in Aarhus. The study was conducted through the general census of Aarhus, by adding a question about father's occupation and father-in-law's occupation, in addition to asking the subject's own occupation. The participants included over 40,000 men. The study was done carefully and objectively. He took all factors and variables into account to ensure validity. Instead of looking at individual relationships for evidence in his analysis, he paid attention to group fluctuations that affected large scale changes in size and social rank of groups and instead of looking at vertical mobility, he looked at mobility between generations, throughout eighteen occupational categories. The main result of the data was a decrease in social mobility over time. In Geiger's analysis, he took these findings to reflect a period of increasing stability following a period of stratification type transition. He attributed this to the democratization of Denmark in the 1930s and 1940s that he claims led to a decrease in the need and desire for upward mobility.