From science to implementation: How do we know if humankind is moving in the right direction towards global sustainability? The ambitious aim of the Sustainable Development Goals (SDGs) is a global call to action to end poverty, protect the planet, and ensure all people enjoy peace and prosperity by 2030.

To monitor progress towards these goals, a set of over 220 indicators is used, but there is a danger that one can no longer see the forest for the trees. A single comprehensive indicator to assess the overall progress is needed.

In a new paper published in the Proceedings of the National Academy of Sciences (PNAS), IIASA researchers and colleagues from the University of Vienna, the Vienna Institute of Demography (Austrian Academy of Sciences), and the Bocconi University present a bespoke indicator based on life expectancy and benchmarks of objective and subjective wellbeing: The Years of Good Life (YoGL) indicator.

“Many existing indicators of wellbeing do not consider the basic fact that being alive is a prerequisite for enjoying any quality of life. In addition, they often disregard the length of a life. Life expectancy has long been used as a very comprehensive indicator of human development, with avoiding premature death being a universally shared aspiration. However, mere survival is not enough to enjoy life and its qualities,” explains lead author Wolfgang Lutz, Founding Director of the Wittgenstein Centre for Demography and Global Human Capital.

“The Years of Good Life indicator only counts a year as a good year if individuals are simultaneously not living in absolute poverty, free from cognitive and physical limitations, and report to be generally satisfied with their lives.”

The results show that YoGL differs substantially between countries. While in most developed countries, 20-year-old women can expect to have more than 50 years of good life left (with a record of 58 years in Sweden), women in the least developed countries can expect less than 15 years (with a record low of 10 years for women in Yemen).

While life expectancy is higher for women than for men in every country, female Years of Good Life are lower than those of males in most developing countries. This reveals a significant gender inequality in objective living conditions and subjective life satisfaction in most of these countries.

The paper — funded by an Advanced Grant to Lutz from the European Research Council — presents a first step in the great challenge to comprehensively assess sustainable human wellbeing that also considers feedbacks from environmental change.

Unlike many other indicators, YoGL is not restricted to the national level but can be assessed for flexibly defined sub-populations and over long-time horizons because it has substantive meaning in its absolute value.

It also has the potential to become a broadly used “currency” for measuring the benefits of certain actions, complementing assessments based on purely monetary units. For example, the social costs of carbon could potentially be evaluated in terms of Years of Good Life lost among future generations, rather than only in dollar terms – making it a key indicator to measure sustainable progress in an integrated and tangible way.

Applying the same logic to the recent COVID-19 pandemic, study coauthor Erich Striessnig adds that YoGL also represents a major improvement over conventional indicators in assessing the long-term success of intervention measures.

“If we used YoGL as a currency to measure the long-term impacts of the ongoing crisis rather than GDP per capita or life expectancy, we would not only account for the material losses and the lost life years, but also for the losses in physical and cognitive wellbeing, as well as for the losses incurred by the younger generations in terms of their human capital resulting from school closures.”

Lack of consistent data that is needed to calculate YoGL does of course remain an issue. Political decision makers should, however, aim for improved data availability to make better informed decisions based on indicators such as YoGL,” Striessnig concludes.