The World Happiness Report is published in partnership with Gallup, the UN Sustainable Development Solutions Network, and an independent editorial board. The dataset used on this site was accessed via Kaggle, which hosts a cleaned CSV version of the 2015 report data; Kaggle is the data source, not the original publisher.
The Survey Method: The rankings are based on the Cantril Ladder: respondents are asked to imagine a ladder with steps numbered 0 to 10, where the top represents the best possible life for them and the bottom the worst, and to say which step they personally feel they stand on. Each country's score is the average response from roughly 1,000 respondents aged 15 or over.
What the Six Factors Actually Mean: The happiness rankings are not calculated from the six factors (GDP, family, health, freedom, generosity, trust). The rankings come entirely from individuals' own assessments. The six factors are used to explain why some countries score higher than others, not to produce the scores themselves. This is a common misconception when reading the data.
The Dystopia Residual: Because the six factors never fully explain a country's score, a seventh value called the Dystopia Residual captures everything left over. "Dystopia" is a hypothetical country with the lowest possible values in every category, used as a baseline so that all components add up to the total happiness score consistently across countries.