1.1 Size of the economy About the data
Definitions
Data sources
About the data
Population, land area, and output are important measurements of economy size. They also
provide a broad indication of actual and potential resources. Therefore, population, land
area, and outputas measured by gross national product (GNP) or gross domestic
product (GDP)are used throughout the World Development Indicators to
normalize other indicators.
Population estimates are generally based on extrapolations from the most recent
national census. See About the data for tables 2.1 and 2.2 for further discussion
on the measurement of population and population growth.
Land area is particularly important for understanding the agricultural capacity of an
economy and the effects of human activity on the environment. See tables 3.1-3.4 for other
measures of land area, rural population density, land use, and productivity. Land area
differs from other measures of geographic size such as surface area, which includes inland
bodies of water and some coastal waterways, and gross area which may include offshore
territorial waters. Recent innovations in satellite mapping techniques and computer
databases have resulted in more precise measurements of land and water areas.
GNP, the broadest measure of national income, measures the total domestic and foreign
value added claimed by residents. GNP comprises GDP plus net receipts of primary income
from nonresident sources. The World Bank uses GNP per capita in U.S. dollars to classify
countries for analytical purposes and to determine borrowing eligibility. See the Users
guide for definitions of the income groups used in this book. Also see About the
data for tables 4.1 and 4.2 for further discussion of the usefulness of national
income as a measure of productivity or welfare.
When calculating GNP in U.S. dollars from GNP reported in national currencies, the
World Bank follows its Atlas conversion method. This involves using a three-year average
of exchange rates to smooth the effects of transitory exchange rate fluctuations. See
Statistical methods for further discussion of the Atlas method. Note that growth rates are
calculated from data in constant prices and national currency units, not from the Atlas
estimates.
Because exchange rates do not always reflect international differences in relative
prices, this table also shows GNP and GNP per capita estimates that are converted into
international dollars using purchasing power parities (PPPs). PPPs provide a standard
measure of real price levels between countries, just as conventional price indexes
calculate real values over time. The PPP conversion factors used here are derived from the
most recent round of price surveyscovering 118 countriesconducted by the
International Comparison Programme (ICP). The surveys, completed in 1996, are based on a
1993 reference year. Estimates for countries not included in the survey are derived from
statistical models using available data. See About the data for tables 4.10 and
4.11 for more information on the ICP and the calculation of PPPs.
Definitions
Population is based on the de facto definition of population, which
counts all residents regardless of legal status or citizenshipexcept for refugees
not permanently settled in the country of asylum, who are generally considered part of the
population of the country of origin. The values shown are midyear estimates for 1996. See
also table 2.1. Land area is a countrys total area, excluding areas
under inland bodies of water. Population density is midyear population
divided by land area in square kilometers. Gross national product (GNP) is
the sum of value added by all resident producers plus any taxes (less subsidies) that are
not included in the valuation of output plus net receipts of primary income (employee
compensation and property income) from nonresident sources. Data are in current U.S.
dollars converted using the World Bank Atlas method (see Statistical methods).
Growth is calculated from constant price GNP in national currency units. GNP per
capita is gross national product divided by midyear population. GNP per capita in U.S.
dollars is converted using the World Bank Atlas method. Growth is calculated from constant
price GNP per capita in national currency units. GNP PPP is gross national
product converted to international dollars using purchasing power parity rates. An
international dollar has the same purchasing power over GNP as the U.S. dollar in the
United States. All ranks are calculated for economies reporting data.
Data sources
Population estimates are prepared by World Bank staff from a variety of sources (see Data
sources for table 2.1). Data on land area are from the Food and Agriculture Organization (see Data
sources for table 3.1). GNP per capita is estimated by World Bank staff based on
national accounts data collected by World Bank staff during economic missions or reported
by national statistical offices to other international organizations such as the OECD. Data for high-income OECD economies come from the
OECD. Purchasing power parity conversion factors are estimates by World Bank staff based
on data collected by the International Comparison Programme.
THE WORLD BANK METHODOLOGY:
----- On External Debt
Definitions
Debt
indicators
----- On WORLD DEVELOPMENT INDICATORS
Size of the economy
Quality of life
Development progress
Trends in long-term development
Long-term structural change
Key indicators for other economies
Population
Land use and deforestation
Growth of output
Credit, investment and expenditures
Integration with the global economy
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