Inequality-Adjusted Happiness in Nations Egalitarianism and Utilitarianism Married in a New Index of Societal Performance

According to the utilitarian creed, the quality of a society should be judged using the degree of happiness of its members, the best society being the one that provides the greatest happiness for the greatest number. Following the egalitarian principle, the quality of a society should rather be judged by the disparity in happiness among citizens, a society being better if differences in happiness are smaller. Performance on these standards can be measured using cross-national surveys, where degree of happiness is measured using the mean response to a question about happiness and disparity expressed as the standard deviation. In this paper we marry these measures together in an index of ‘Inequality-Adjusted Happiness’ (IAH) that gives equal weight to either criterion. It is a linear combination of the mean happiness value and the standard deviation and it is expressed as a number on a 0–100 scale. We applied this index to 90 nations for the 1990s and observed large and systematic differences, IAH being higher in rich, free and well-governed countries. We also considered the trend over time for 14 rich countries and found that IAH has increased over the last 30 years.