The United Nations (UN) compiles data and prepares statistics on the world population and its evolution, providing information on such diverse demographic variables as number of people per country, population growth, projections, birth rate, mortality and migration. The OECD provides information on migration, asylum requests and the acquisition of nationality.

The most up-to-date and complete information on this topic is available at the UN Statistics Division webpage, specially at the database, and at the OECD website.
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