PER-HAPPINESS-INDEX

Life evaluations from the Gallup World Poll provide the basis for the annual happiness rankings. They are based on answers to the main life evaluation question. The Cantril Ladder asks respondents to think of a ladder, with the best possible life for them being a 10 and the worst possible life being a 0. They are then asked to rate their own current lives on that 0 to 10 scale. The rankings are from nationally representative samples over three years. Data are observed on the six variables and estimates of their associations with life evaluations to explain the variation across countries. They include GDP per capita, social support, healthy life expectancy, freedom, generosity, and corruption. Happiness rankings are not based on any index of these six factors – the scores are instead based on individuals’ own assessments of their lives, in particular, their answers to the single-item Cantril ladder life-evaluation question, much as epidemiologists estimate the extent to which life expectancy is affected by factors such as smoking, exercise, and diet.