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Notes and Definitions
In addition to the updating of information, the following changes have been made in this edition of The World Factbook. The name Wake Island has been officially changed to Wake Atoll. The Historical perspective and Current issues entries in the Introduction category have been combined into a new Background entry. It appears in only a few country profiles at this time. There are new entries on Population below poverty line, Household income or consumption by percentage share, Electricity—production by source (fossil fuel, hydro, nuclear, other), Electricity—exports, and Electricity—imports. A new reference map of Kosovo has been included and terrain has been added to most of the reference maps.
Abbreviations: This information is included in Appendix A: Abbreviations, which includes all abbreviations and acronyms used in the Factbook, with their expansions.
Administrative divisions: This entry generally gives the numbers, designatory terms, and first-order administrative divisions as approved by the US Board on Geographic Names (BGN). Changes that have been reported but not yet acted on by BGN are noted.
Age structure: This entry provides the distribution of the population according to age. Information is included by sex and age group (0-14 years, 15-64 years, 65 years and over). The age structure of a population affects a nation's key socioeconomic issues. Countries with young populations (high percentage under age 15) need to invest more in schools, while countries with older populations (high percentage ages 65 and over) need to invest more in the health sector. The age structure can also be used to help predict potential political issues. For example, the rapid growth of a young adult population unable to find employment can lead to unrest.
Agriculture—products: This entry is a rank ordering of major crops and products starting with the most important.
Airports: This entry gives the total number of airports. The runway(s) may be paved (concrete or asphalt surfaces) or unpaved (grass, dirt, sand, or gravel surfaces), but must be usable. Not all airports have facilities for refueling, maintenance, or air traffic control.
Airports—with paved runways: This entry gives the total number of airports with paved runways (concrete or asphalt surfaces). For airports with more than one runway, only the longest runway is included according to the following five groups —(1) over 3,047 m, (2) 2,438 to 3,047 m, (3) 1,524 to 2,437 m, (4) 914 to 1,523 m, and (5) under 914 m. Only airports with usable runways are included in this listing. Not all airports have facilities for refueling, maintenance, or air traffic control.
Airports—with unpaved runways: This entry gives the total number of airports with unpaved runways (grass, dirt, sand, or gravel surfaces). For airports with more than one runway, only the longest runway is included according to the following five groups—(1) over 3,047 m, (2) 2,438 to 3,047 m, (3) 1,524 to 2,437 m, (4) 914 to 1,523 m, and (5) under 914 m. Only airports with usable runways are included in this listing. Not all airports have facilities for refueling, maintenance, or air traffic control.