EARTHTRENDS DATA TABLES TECHNICAL NOTES: Population and Education 2005 For more information, please consult http://earthtrends.wri.org DEFINITIONS AND METHODOLOGY Total Population refers to estimates and projections of de facto population as of July 1 of the year indicated. Percent of Population under Age 15 is the proportion of the total population younger than 15 years of age. Percent of Population Age 65 and Over is the proportion of the total population 65 years of age and older. Total Fertility Rate is an estimate of the average number of children a woman would have over the course of her entire life if current age-specific fertility rates remained constant during her reproductive years. The four variables defined above are estimated by the United Nations Population Division (UNPD) for the years 1950-2000 and forecasted based on the assumptions enumerated below for the years 2001-2050. Past estimates are calculated using census and survey results from all countries. The UNPD compiles, evaluates, and adjusts these data when necessary. Adjustments incorporate data from civil registrations (in developed countries), population surveys (in developing countries), earlier censuses, and, when necessary, population models based on information from similar countries. The projections reported here assume medium fertility (the "medium-fertility assumption"). All future population projections are based on estimates of the 2000 base-year population and incorporate the three main components of population growth: fertility, mortality, and migration. Fertility is estimated by applying age-specific fertility rates to the projected female population using models based on past trends in fertility to project future declines. Mortality is projected on the basis of the models of life expectancy that assume a medium pace of mortality decline. For countries affected by the HIV/AIDS epidemic, mortality rates are predicted using a model developed by the Joint United Nations Program on HIV/AIDS (UNAIDS). Migration rates are estimated on the basis of past international migration estimates and an assessment of the policy stance of countries with regard to future international migration flows. The UNPD incorporates information on official immigration and emigration, labor migration, undocumented migration, and refugees. For more information on methodology, see World Population Prospects, 2002 Revision. Volume III: Analytical Report. Online at http://www.un.org/esa/population/publications/wpp2002/WPP2002_Vol3.htm. Mortality under Age 5 is the probability of a child dying between birth and age five expressed per 1,000 live births. Data for estimating mortality of children under age 5 is typically obtained from population census information, civil registration records on deaths of young children, United Nations Childrens' Fund (UNICEF) Multiple Indicator Cluster Surveys (MICS) and Demographic and Health Surveys (DHS). For each country, UNICEF and its partners plotted all data from 1960 to the present on a graph; a curve was fitted through these data using a weighted least-squares regression model. Refugees Granted Asylum Elsewhere is the number of refugees leaving a country who have been granted asylum status by a foreign government. Refugees Repatricians is the number of refugees who have successfully returned (repatriated) to their home country. In both columns, refugees are counted according to their home countries (“country of origin”), not their country of asylum. Data were collected in 2003 but include all persons that have migrated as refugees without returning to their home country. According to Article 1 of the 1951 Convention Relating to the Status of Refugees and the related 1967 Protocol, a refugee is a person who "owing to a well-founded fear of being persecuted for reasons of race, religion, nationality, membership of a particular social group or political opinion, is outside the country of his nationality and is unable to or, owing to such fear, is unwilling to avail himself of the protection of that country." This variable reflects the number of refugees recognized by the United Nations High Commissioner for Refugees (UNHCR), which generally relies on host government reporting to obtain data, supplemented with information collected by aid workers. Internally Displaced Persons (IDPs) are defined by the United Nations as “persons or groups of persons who have been forced or obliged to flee or to leave their homes or places of habitual residence, in particular as a result of or in order to avoid the effects of armed conflict, situations of generalized violence, violations of human rights or natural or human-made disasters, and who have not crossed an internationally recognized State border." The UNHCR estimates that globally there are 25 million internally displaced people in over 50 countries. Since they have not crossed into another country, IDPs are generally not afforded the same protections and assistance given to refugees. Estimates are from the Global IDP Project and incorporate a wide variety of sources, including non-governmental organizations (NGOs), academic research, governments, and news agencies. Literacy Rates measure the proportion of the population in a specific age group who can both read and write with understanding a short, simple statement on their everyday life. Adult Literacy Rates refer to all residents of a country or region over the age of 15; Youth Literacy Rates evaluate the population of a country between the ages of 15 and 24 in the year specified. Youth literacy rates are increasingly used to gauge the impact of primary education as well as the speed with which illiteracy can be eradicated. Most literacy data are collected during national population censuses and supplemented by household surveys, labor force surveys, employment surveys, industry surveys, and agricultural surveys when they are available. UNESCO uses these data to graph a logistic regression model. When census and survey data are not available, literacy rates for a specific country are estimated based on neighboring countries with similar characteristics. Net School Enrollment Ratio (NER) is defined as the enrollment of the official age group for a given level of education expressed as a percentage of the population from the same age group. The theoretical maximum value is 100 percent. A high NER denotes a high degree of participation of the official school-age population. If the NER is below 100 percent, users should not assume that the remaining school-age population is not enrolled in any school; they could be enrolled in school at other grade levels. Primary Education is defined by the International Standard Classification of Education (ISCED) as the "beginning of systematic apprenticeship of reading, writing and mathematics." Programs are typically six years long and represent the beginning of compulsory education in many countries. Secondary education follows primary education, and is characterized as being subject-oriented with specialized fields of learning. Students achieve a full implementation of basic skills. Programs may be academic, vocational, or technical in nature. Net enrollment ratio is calculated by dividing the number of pupils enrolled who are of the official age group for a given level of education by the total population of the same age group. National governments provide the United Nations Educational, Scientific, and Cultural Organization (UNESCO) with enrollment data based on a series of electronic questionnaires. When data from national governments are not available or are of inferior quality, UNESCO will estimate enrollment ratios from background data, if available. FREQUENCY OF UPDATE BY DATA PROVIDERS Both UNPD and UNAIDS publish country-level statistics every two years with annual revisions of key estimates. UNICEF and UNHCR publish the most recently available data in an annual report, with more frequent updates online. Education, literacy and IDP data are updated irregularly. Most updates include revisions of past data. DATA RELIABILITY AND CAUTIONARY NOTES Total Population, Fertility, and Life Expectancy. Since demographic parameters are estimated on a country-by-country basis, reliability varies among countries. For some developing countries, estimates are derived from surveys rather than censuses, especially when countries lack a civil registration system or have one that does not achieve full coverage of all vital events. Also, for developing countries the availability of detailed information on fertility and mortality is limited and the data on international migration flows are generally inadequate. Although estimates are based on incomplete data and projections cannot factor in unforeseen events (i.e., famine, wars), U.N. demographic models are widely accepted and use well-understood principles, which make these data as comparable, consistent across countries, and reliable as possible. Mortality Under Age 5: Estimates were calculated based on a wide variety of sources of disparate quality. For information on the underlying data for each country's regressions, refer to the country estimates and new country data available from UNICEF online at http://www.childinfo.org/cmr/kh98meth.html. Refugees: Since the determination of refugee status varies among countries, UNHCR will estimate numbers in order to provide a normalized dataset. Data are "provisional and subject to change," and accuracy is limited by the politically sensitive nature of refugee estimates and the circumstances under which many refugees live. UNHCR attempts to harmonize the data in order to allow cross-country comparisons. Internally Displaced Persons: Due to the highly political nature of displacement and the conditions in which many displaced peoples find themselves, accurate data are difficult to collect. While the numbers presented are broad estimates, these data are the best Online on the topic. Adult Literacy Rate: The availability and quality of national statistics on literacy vary widely. National census and survey data are typically collected only once every decade. In addition, many industrialized countries have stopped collecting literacy data in recent years, based on the sometimes incorrect assumption that universal primary education means universal literacy. When census and survey data are not available for a particular country, estimates are sometimes made based on neighboring countries. Actual definitions of adult literacy are not strictly comparable among countries. Some countries equate persons with no schooling with illiterates, or change definitions between censuses. In addition, UNESCO's definition of literacy does not include people who, though familiar with the basics of reading and writing, do not have the skills to function at a reasonable level in their own society. Net School Enrollment: Even though UNESCO has applied the same methodology to analyze all of the country data, definitions of "schooling" and "enrollment" are not strictly comparable among countries. As net enrollment ratios approach 100 percent, inconsistencies with enrollment and/or population data are more likely to skew the resulting ratios. As a result, some net enrollment ratios are greater than 100 percent. Difficulties also arise when a substantial proportion of students begin school earlier than the prescribed age, or when the reference date for entry into primary education does not coincide with the birthdays of all eligible students. SOURCES Total Population, Fertility, and Life Expectancy: United Nations Population Division. 2003. World Population Prospects: The 2002 Revision. Dataset on CD-ROM. New York: United Nations. Online at http://www.un.org/esa/population/ordering.htm. Mortality under Age 5: United Nations Children's Fund (UNICEF). 2004. State of the World's Children: Girls, Education, and Development. New York: UNICEF. Online at http://www.unicef.org/sowc04/. Net Refugee Migration: United Nations High Commissioner for Refugees (UNHCR). 2004. Global Refugee Trends: Overview of Refugee Populations, New Arrivals, Durable Solutions, Asylum-Seekers and Other Persons of Concern to UNHCR. Geneva: UNHCR. Online at http://www.unhcr.ch/statistics. Internally Displaced Persons: Global IDP Project. 2004. Internal Displacement: A Global Overview of Trends and Developments in 2003. Geneva: Norwegian Refugee Council. Online at http://www.idpproject.org/global_overview.htm. Adult Literacy Rate and Net School Enrollment Ratio: United Nations Educational, Scientific, and Cultural Organization (UNESCO) Institute for Statistics. Literacy Rates by Country and by Gender, July, 2004 Revision. Paris: UNESCO. Online at http://www.uis.unesco.org/.