That measure doesn't deal with over population, which is a huge thing, and more likely to run out of control than consumption per person in a country. Although

That measure doesn't deal with over population, which is a huge thing, and more likely to run out of control than consumption per person in a country. Although individual consumption is important as well. For instance New Delhi is far more polluted than any US city, although energy consumption per capita may be 16 times more in the US than India. In my opinion a measure like energy or resource use per square kilometer of land is a much better measure. Although it has its problems as well, such as land quality varying greatly between different areas, which would change the number of people an area of land could support in a sustainable way. Sources: Population and energy usage per country http://www.worldpopulationbalance.org/population_energy http://www.worldpopulationbalance.org/population_energy . This uses Population Reference Bureau; 2012 World Population Data Sheet for population information and uses U.S. Energy Information Administration 2012 for energy use information. This is on the bottom of the page linked. For the Pollution index, it is Pollution Index 2016 Mid Year http://www.numbeo.com/pollution/rankings.jsp http://www.numbeo.com/pollution/rankings.jsp . Disclaimer: I am not an expert in the slightest.