Data Sources

A description of the empirical data used and the methods applied in revising past estimates of population and components of demographic change (fertility, child, adult and overall mortality, international migration) is available here for each country or area for the period 1950 to 2023. For the countries with less than 1,000 inhabitants in 2023, only the data sources for total population are made available.

Select below a country or area to see the respective information, or download the whole set of metadata in PDF format for all countries or areas or a tabular version for each demographic component under Documentation.

Maldives

Population: Total population and distribution by age and sex estimated to be consistent with the population by age and sex of the (a) 1965, 1967, 1974, 1977, 1985, 1990, 1995, 2000, 2006, 2014, 2022 censuses; (b) adjusted for under/over count; (c) adjusted for age heaping; (d) adjusted for under enumeration of children under age 15; (e) 2009, 2016-2017 DHS survey estimates; (f) official estimates through 2021; (g) only total population for 1946, 1953, 1956, 1957, 1958, 1959, 1962, 1972 censuses; and with estimates of the subsequent trends in fertility, mortality and international migration.  In addition, the population register through 2017 have been considered.

Fertility: Total fertility rate and age pattern of fertility based on: (a) official estimates of age-specific fertility rates through 2014; (b) registered births classified by age of mother and the underlying female population by age through 2021; (c) birth-histories data from the 2009, 2016-2017 DHS; (d) births in the household in the preceding 12 (or 24) months classified by age of mother from the 1990, 2000, 2006, 2014 censuses; (e) adjusted fertility using Arriaga modified P/F ratio method with data on children ever born and births in the preceding 12 (or 24/36) months, both classified by age of mother, from the 2006 Census; (f) indirect estimates obtained using Mortara's method with data on children ever born by age of mother from the 1985 Census; (g) indirect estimates obtained from the application of the reverse survival method to the 1967, 1974, 1977, 1985, 1990, 1995, 2000, 2006, 2014 censuses; (h) indirect estimates obtained from the application of the own-children method of fertility estimation to the 1995, 2000 censuses; (i) indirect estimates obtained from stable population assumption; (j) cohort-completed fertility backdated by the mean age of childbearing from the 1977, 1990, 1995, 2000, 2006 censuses and 2009, 2016-2017 DHS.  In addition, the (a) adjusted fertility using Arriaga modified P/F ratio method with data on children ever born and births in the preceding 12 (or 24/36) months, both classified by age of mother, from the 1977 Census; (b) indirect estimates obtained using Mortara's method with data on children ever born by age of mother from the 1977 Census; (c) indirect estimates obtained from the application of the reverse survival method to the 1977-2010 Education Stats; (d) cohort-completed fertility backdated by the mean age of childbearing from the 1985 Census have been considered.

Child Mortality: Under-five mortality based on: (a) official estimates of infant and child mortality through 2017; (b) registered infant and child deaths through 2021; (c) direct estimates from births and deaths under-five calculated from full birth histories data from the 2009, 2016-2017 DHS; (d) indirect estimates from data on children ever born and surviving from the 1977, 1985, 1990, 1995, 2000, 2006 censuses and 1997-1998, 2004 VPA and 2004 RHBS; (e) International estimates used up to 2021.

Overall Mortality: Life expectancy at birth and age pattern of mortality based on: (a) official estimates through 2007; (b) registered deaths by age and sex available through 2021; (c) adjusted for underreporting of infant and child deaths; (d) adult deaths adjusted for underregistration using death distribution methods; (e) mortality rates for older ages were adjusted; (f) estimates using CD West model life tables and estimates of under-five mortality (5q0), and adult mortality (45q15).

Adult and Old Age Mortality: Estimates derived from: (a) deaths by age and sex available from Register through 2020; (b) adjusted for underregistration; (c) maternal orphanhood from the 2009 DHS; (d) paternal orphanhood from the 2009, 2016-2017 DHS; (e) intercensal survivorship from successive census age distributions; (f) estimates of under-five, adult and old age mortality.  In addition, the (a) maternal orphanhood from the 2016-2017 DHS; (b) indirect estimates of male adult mortality based on female widowhood data from the 1977, 1985, 1990, 1995, 2000, 2006, 2014 censuses and 2009, 2016-2017 DHS; (c) indirect estimates of female adult mortality based on male widowhood data from the 1977, 1985, 1990, 1995, 2000, 2006 censuses; (d) intercensal survivorship from successive census age distributions have been considered.

Migration: International migration based on: (a) information on foreign-born populations from censuses and registers from major countries of destination; (b) estimates derived as the differences between overall population growth and natural increase; (c) UNHCR statistics on the number of refugees in the main countries of asylum.

Disclaimer: This web site contains data tables, figures, maps, analyses and technical notes from the current revision of the World Population Prospects. These documents do not imply the expression of any opinion whatsoever on the part of the Secretariat of the United Nations concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries.