Explain how Human Development Index is calculated?

Human Development Index is a composite index prepared by the United Nations Development Programme on a scale 0-1 measured on the basis of three indicators.
(i) **Longevity—**It implies how long a newborn is expected to live.
(ii) **Knowledge or Educational Attainment—**It implies the status of education of the people. It includes
**Adult Literacy Rate—**It refers to percentage of people above 15 years of age who can read and write.
**Gross Enrolment Ratio—**It refers to estimation of number of students enrolled for different levels of education such as primary, secondary and tertiary levels is estimated.

(iii) Income (Per capita Real GDP). It implies purchasing power of people or their capacity to buy goods and services.

Human Development Index is estimated by taking the simple average of the three indices. Different countries are rated between 0 to 1.177. Countries have been covered for this index. HDI measures the economic welfare in a particular country. In 2004, India ranked 126 in the world.