The Human Development Index ranks the countries based on their performance in the key areas of health, education and access to resources. These ranking are based on a score between 0 to 1, that a country earns from it record in the key areas of human development. Each of these dimensions is given a weightage of 1 / 3. The HDI is the sum total of the weights assigned to all these dimensions. The closer a score is to 1, the greater is the level of human development.