Human Development Index (HDI)
A composite index used by the UNDP to measure a country’s development.
(United Nations Development Program (UNDP). "Human Development Reports FAQs." http://hdr.undp.org/en/statistics/faq; UNDP. 2000. Human Development Report 2000. New York: Oxford University Press, p. 17. http://hdr.undp.org/en/media/HDR_2000_EN.pdf.)
1) The HDI – human development index – is a summary composite index that measures a country's average achievements in three basic aspects of human development: health, knowledge, and a decent standard of living. Health is measured by life expectancy at birth; knowledge is measured by a combination of the adult literacy rate and the combined primary, secondary, and tertiary gross enrolment ratio; and standard of living by GDP per capita (PPP US$).
2) The HDI measures the average achievements in a country in three basic dimensions of human development—a long and healthy life, knowledge and a decent standard of living. A composite index, the HDI thus contains three variables - life expectancy at birth, educational attainment (adult literacy and the combined gross primary, secondary and tertiary enrolment ratio) and GDP per capita (PPP US$). Income enters the HDI as a proxy for a decent standard of living and as a surrogate for all human choices not reflected in the other two dimensions.