There have been two Mikrozensus surveys on the occupational history (in 1972, Mikrozensus MZ7203 and 1982, Mikrozensus MZ8202). This can be best achieved by recording all phases of the complete occupational history. One phase is defined as follows: A period over which the branch of industry, the job and the qualifications have remained the same. If one of these three factors has changed, a new phase has started. A temporary or lasting withdrawal from working life also counts as a new phase. The target group of this survey are all persons born between the years 1926 and 1981 (15- to 70-year-olds). This age-frame was chosen to not only interview employed persons (including self-employed persons and those helping in the family business) on their occupational history. Currently unemployed persons as well as all other non-working persons - who had worked once - were asked about their previous occupational history. Thereby retired persons were also included which is the only possibility to gain information on completed occupational histories.