..."Densely inhabited districts are contiguous census districts with high population density (in principle, 4,000 inhabitants or more per square kilometer) within...or village constituting an agglomeration of 5,000 or more inhabitants. 'Population of densely inhabited districts as a percentage of Japan's total population....

...into new shi (cities), the old definition of urban and rural areas had become unsatisfactory. A DlD is defined as a group of contiguous census-enumeration...more per square kilometer) within the boundary of a shi, a ku (ward), a machi, or a mura constituting an agglomeration of 5,000 inhabitants or more. DlDs...