Population Density
Temporal Info: 
Population per sq. km
UN 2015

Population Division of the Department of Economic and Social Affairs of the United Nations Secretariat, World Population Prospects: The 2015 Revision, http://esa.un.org/unpd/wpp/Excel-Data/population.htm

Population density is total number of people per square kilometer of land area residing within a country in a given year. The data is compiled by the United Nations Population Division (UNPD) using census and survey results from each countries. One should keep in mind that data reliability varies among countries, but the U.N. demographic models are widely accepted because they employ well-understood assumptions.