The special survey in March is on the topic of extended housing survey ("Erweiterte Wohnungserhebung"), just as in the previous years (Mikrozensus MZ7001 and MZ6901) In addition, there are a few questions on intentions of housing. They resemble the questions of the special survey “Wohnungswechsel” (change of residence) in June 1969 (Mikrozensus MZ6902) and aim at complementing the then collected data with new information.