The UN’s famous Human Development Index (HDI) is a little over 20 years old. Of all the world’s indices, the HDI is surely one of the most widely cited. It ranks countries by the quality of life they give to their people. Its brilliance lies in its simplicity.

According to the index, three traits govern human development and quality of life: wealth, health and education. The wealth of a nation is measured each year by Gross National Income (it used to be measured by Gross National Product), health is quantified by citizens’ longevity (life expectancy at birth), and the number of years of schooling indicates education.

One major problem with this measure is that it totally neglects sustainability or environmental wellbeing. It is an open secret that we are in a sustainability crisis, with approximately 52% of wild animals having died off in the last 40 years and the current extinction rate hovering roughly around 1000x the background rate. If we are going to rank development, I think we can all agree we should rank sustainable development above unsustainable development.

After the release of last year’s HDI, Chuluun Togtokh recalculated the index, while including one extra trait: per capita carbon emissions. Although this isn’t as accurate a measure as looking at a more in-depth environmental footprint which includes biodiversity and resource use, it is simple and easy to measure. Like using longevity as an indicator of health, sticking with carbon emissions keeps the calculation simple and reasonably objective.

Here is the HDI (Human Development Index) contrasted with the HDSI (Human Development Sustainability Index):


Notice how the U.S. drops from 4th to 24th if we include even this single environmental factor.


Before anyone gets angry and sends my a message about how the United States is improving in its sustainability, or that it isn’t as bad as China: only the second statement is probably true. But even if the first statement was correct, it is important to remember that it isn’t simply the existence of change, but rather the extent and depth of this change, which we can use to qualify which countries are acting more responsible than they were.


After 20 years of the HDI, it has become clear there are no quick fixes for improving a country’s quality of life. Progress emerges through long-term sustained policy changes. The US only slowly improved its standing in the HDI with an average increase of 1/4 of a percentage point per year.

Likewise, global sustainability is a long-term challenge. The big changes will be made by thinking sustainably now when making decisions on where and how to build roads and transport links, power plants, fields, housing and the rest of the infrastructure needed to support the world’s heaving population over the next forty years and beyond.

The original HDI encouraged people to reconsider the meaning of national development, and its use lies in its ability to clearly display the impact of long-term policy interventions. Now that the global context has changed, the UN must be careful of sending out the wrong signal regarding what is “proper” or “advantageous” behavior. Certainly, it’s worth acknowledging that sustainability is at least as important as Gross National Income, right?