Education is one of the topics included in the Human Development Index calculated by the UN. This measure is “a composite index measuring average achievement in three basic dimensions of human development—a long and healthy life, knowledge and a decent standard of living.” This map shows the average number of years of education received by people aged 25 and older. The 30 largest countries of the world by population are listed. Note the variation in education levels in each continent of the world, with the lowest levels in parts of Africa and Asia.