Inhabitants per square kilometre, inv/number

Number of inhabitants 31/12 years T divided by land area 1/1 year T+ 1, square kilometers. The land area includes watercourses 6 meters and narrower as well as ponds and smaller water collections, up to a maximum of a few 10 square meters.截至T年12月31日的居住人口数，除以T+1年度的陆地面积（单位：平方千米）。该陆地面积包含宽度6米及以下的水道，以及最大面积不超过数十平方米的池塘与小型积水区域。