- Airports: Total number of airports. Runways must be useable, but may be unpaved. May not have facilities for refuelling, maintenance, or air traffic control.
- Gross value added by transport, storage and communication: Gross Value Added by Kind of Economic Activity at current prices - US dollars.
- Highways > Total > Per capita: total length of the highway system Per capita figures expressed per 1,000 population.
- Motor vehicles: Motor vehicles per 1,000 people
- Motor vehicles > Per 1,000 people: Motor vehicles include cars, buses, and freight vehicles but do not include two-wheelers. Population refers to midyear population in the year for which data are available."
- Passenger cars > Per 1,000 people: Passenger cars refer to road motor vehicles, other than two-wheelers, intended for the carriage of passengers and designed to seat no more than nine people (including the driver)."
- Rail > Railway length: Railway length in kilometers.
Road > Motor vehicles per 1000 people:
Motor vehicles per 1000 people.
No date was available from the Wikipedia article, so we used the date of retrieval.
- Road > Motorway density: Meters of motorway per square kilometer.
- Road > Motorway length: Total network length of all motorways in km.
- Road density > Km of road per 100 sq. km of land area: Road density is the ratio of the length of the country's total road network to the country's land area. The road network includes all roads in the country: motorways, highways, main or national roads, secondary or regional roads, and other urban and rural roads."
- Road network length > Km: Length of road network in kilometers in European Union countries.
- Roads > Passenger cars > Per 1,000 people: Passenger cars (per 1,000 people). Passenger cars refer to road motor vehicles, other than two-wheelers, intended for the carriage of passengers and designed to seat no more than nine people (including the driver).
- Vehicles > Per km of road: Vehicles per kilometer of road include cars, buses, and freight vehicles but do not include two-wheelers. Roads refer to motorways, highways, main or national roads, secondary or regional roads, and other roads. A motorway is a road specially designed and built for motor traffic that separates the traffic flowing in opposite directions."
- Waterways: The total length and individual names of navigable rivers, canals, and other inland bodies of water.
SOURCES: CIA World Factbooks 18 December 2003 to 28 March 2011; United Nations Statistics Division; All CIA World Factbooks 18 December 2003 to 18 December 2008; United Nations World Statistics Pocketbook and Statistical Yearbook; International Road Federation, World Road Statistics and data files.; Wikipedia: List of countries by rail transport network size (Long List); Wikipedia: List of countries by vehicles per capita; https://www.cia.gov/library/publications/the-world-factbook/fields/2085.html, Roadways.; International Road Federation, World Road Statistics and electronic files, except where noted.