Human Development Index

The HDI was introduced in 1990, partly inspired by economists Mahbub ul Haq and Amartya Sen, to shift attention from income alone to people’s broader wellbeing.

It combines three dimensions: a long and healthy life, measured by life expectancy at birth; knowledge, measured by expected and average years of schooling; and a decent standard of living, measured by gross national income per person, adjusted for purchasing power. Each is converted into an index, and the results are combined into a single score between 0 and 1.

For example, two countries with similar income per person may have quite different HDI scores if one has much better health and education outcomes.

The HDI is widely used to compare countries and track progress over time. Critics note that it simplifies complex realities, ignores inequality within countries and leaves out factors such as environmental sustainability. Related measures adjust the HDI for inequality and environmental pressures.