The Human Development Index (HDI) is a statistical composite index that measures the average achievements in three basic dimensions of human development: a long and healthy life, access to knowledge, and a decent standard of living. It was created by the United Nations Development Programme (UNDP) in 1990 to emphasize that people and their capabilities should be the ultimate criteria for assessing the development of a country, not economic growth alone. The HDI is calculated using the following indicators:

• Life expectancy at birth
• Mean years of schooling for adults aged 25 years and more
• Expected years of schooling for children of school entering age
• Gross national income (GNI) per capita in purchasing power parity (PPP) terms in US dollars

The HDI is the geometric mean of normalized indices measuring achievements in each dimension, with each dimension index contributing equally to the final score. The HDI can be used to compare countries and to question national policy choices, asking how two countries with the same level of GNI per capita can end up with different human development outcomes. However, the HDI has been criticized for its alleged lack of consideration of technological development or contributions to human civilization, focusing exclusively on national performance and ranking, and lack of attention to development from a global perspective.