Human Development Indices and Indicators 2018

The cover reflects human development progress over 1990–2017 in terms of Human Development Index (HDI) values and the number of people in the four human development categories. In the figure each slice’s innermost band represents the population in that human development category, and the height of the slice reflects its HDI value. The cover reflects that even though the global population increased from 5 billion to 7.5 billion between 1990 and 2017, the number of people in low human development fell from 3 billion to 926 million—or from 60 percent of the global population to 12 percent—and that the number of people in high and very high human development more than tripled, from 1.2 billion to 3.8 billion—or from 24 percent of the global population to 51 percent.