what does population density
What Is Population Density? - Definition & Measurements Population density is a measurement of the number of people in an area relative to its size. Population density is often quantified as arithmetic density, physiological density, and agricultural density. Population density Population density. The population density of a country or city or other place is a number showing how crowded that place is. It is calculated by dividing the population by the area. For example, France has a population of 60,561,200, and an area of 551,695 square kilometres, so its population density is about 109.8 persons per square kilometre. A number of factors can affect population density. For example, the climate.