The lack of a global definition of urban and rural areas is a well-known obstacle to reliable international comparisons of urbanisation and of the situation in the urban and rural areas. Data collections, such as the World Urbanization Prospects published by the UN Population Division are based on national definitions and national administrative designations. These definitions vary widely and are difficult if not impossible to replicate in another country. The administrative designation of urban and rural areas means that they are simply selected without a definition, which makes it impossible to judge how comparable they are.1

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The Degree of Urbanisation identifies three types of settlements (known as level 1):

  • Cities, which have a population of at least 50,000 inhabitants in contiguous dense grid cells (>1,500 inhabitants per km2);
  • Towns and semi-dense areas, which have a population of at least 5,000 inhabitants in contiguous grid cells with a density of at least 300 inhabitants per km2; and
  • Rural areas, which consist mostly of low-density grid cells.

This definition can be extended in two ways: the Degree of Urbanisation level 2 and the Functional Urban Area definition. The Degree of Urbanisation level 2 identifies smaller settlements by defining: cities, towns, suburban or peri-urban areas, villages, dispersed rural areas, and mostly uninhabited areas. The Functional Urban Area Definition creates metropolitan areas by adding a commuting zone around each city. The full detail of the Degree of Urbanisation and its two extensions can be found in section 7 of a new manual which is currently in open consultation and due for publication in November.

  • 1. Several recent global agendas call for the collection of indicators for cities, urban, and rural areas: the 2030 Agenda for Sustainable Development (UN 2015), the New Urban Agenda (UN-Habitat 2017), and the Global Strategy to Improve Agricultural and Rural Statistics (IBRD-WB 2011). Basing these indicators on a harmonized definition would facilitate international comparisons and improve the quality of rural and urban statistics in support of national policies and investment decisions.

    That is why six international organizations, the European Union, The Food and Agriculture Organization of the United Nations (FAO), the International Labour Office (ILO), the Organization for Economic Co-operation and Development (OECD), the United Nations Human Settlements Programme (UN-Habitat), and the World Bank, have worked closely together to develop a harmonized definition. In March 2020, the researchers presented the work to the UN Statistical Commission, which endorsed it. In June 18, 2020, the European Union and OECD launched the group’s report, Cities of the World, A New Perspective on Urbanisation (OECD 2020) that describes the use of and technical background of the new definition, the Degree of Urbanisation.