Development can be measured by economic or human factors. Developing countries are, in general, countries that have not achieved a significant degree of industrialization relative to their populations, and have, in most cases, a medium to low standard of living. There is an association between low income and high population growth. The development of a country is measured with statistical indices such as income per capita (per person), gross domestic product per capita, life expectancy, the rate of literacy, freedom index and others. The UN has developed the Human Development Index (HDI), a compound indicator of some of the above statistics, to gauge the level of human development for countries where data is available. The UN had set Millennium Development Goals from a blueprint developed by all of the world's countries and leading development institutions, in order to evaluate growth. These goals ended in 2015, to be superseded by the Sustainable Development Goals.