This are pseudonymous data of "Aktion Forscherkontakte" (FOKO) of the Deutschen Arbeitsgemeinschaft Genealogischer Verbände (DAGV, = German association of genealogical associations), which was operated by the Verein für Computergenealogie (=association for computer genealogy). For over 25 years the DAGV has collected information on geographical and temporal distribution of family names. Amateur genealogists have been invited to submit the names of researched family in aggregated form. In this way, nearly 1.28 million evidence of names were collected. A record includes the following information: family name year of first evidence year of last evidence - Occasionally you will find the value 9999 for 'today' which can be interpreted at least as 1990. submitter (pseudonymous) denomination country territory postal code or "w-Nummer" (replacement zip in German registry offices) place name place identificator For denomination, country and territory specific abbreviations are used, which can be looked up in the CSV files. Some of the identifiers for country and territory are a bit idiosyncratic from project-historical reasons.