Abstract
The chapter covers the development of administrative divisions from the 1920s to the present. It is included to inform readers about basic changes in the system of districts and also touches on the collection and processing of statistical data.
Administrative maps are also processed for census years and show the district system for that year, as well as corresponding to the base used the atlas as a whole. In addition, this chapter includes historical administrative maps selected in order to show significant changes in the system of districts.