A mainline is normally identified by a unique number that is the one billed. Waiting time shows the approximate number of years applicants must wait for a telephone line. It is calculated by dividing the number of applicants on the waiting list by the average number of mainlines added per year over the past three years. Outgoing traffic refers to the telephone traffic, measured in minutes per subscriber, that originated in the country with a destination outside the country. Average price per call is the cost of a three-minute peak rate call from any country to the United States.
Paved roads are roads that have been sealed with asphalt or similar road-building materials.
Normalized road index is the total length of roads in a country compared with the expected length of roads, where the expectation is conditioned on population, population density, per capita income, urbanization, and regional-specific dummy variables. If the index is more than 100, the country's stock of roads exceeds the average. Goods transported by road are the volume of goods transported by road vehicles, measured in millions of metric tons times kilometers traveled. Goods transported by rail are the tonnage of goods transported times kilometers traveled. Aircraft departures are the number of domestic and international takeoffs of aircraft.