Rail ridership is usually measured in passenger-kilometres one passenger-kilometre represents one passenger travelling one kilometre.One 1,000-person train travelling 1,000 kilometres would on its own account for a million passenger-kilometres.Yet American railroads accounted for just 17.2 billion passenger-kilometres in 2010 according to Amtrak,America's government-backed passenger rail corporation.In the European Union,railways accounted for nearly 400 billion,according to International Union of Railways data.When you adjust for population,the disparity is even more shocking: per capita,the Japanese the Swiss the French the Danes the Russians the Austrians the Ukrainians the Belarussians and the Belgians all accounted for more than 1,000 passenger-kilometres by rail in 2011;Americans accounted for 80.Amtrak carries 31 m passengers per year.Mozambique's railways carried 108m passengers in 2011.There are mary reasons why Americans don't ride the rails as often as their Europen cousins.Most obviously America is bigger than most Europen countries.Outside the northeast corridor the central Texas megalopolis California and the eastern Midwest density is sometimes too low to support intercity train travel.Underinvestment and a preference for shiny new visions over boring upgrades has not helped.Most American passenger trains travel on tracks that are owned by freight companies.That means most trains have to defer to freight services leading to lengthy delays that scare off Passengers who want to arrive on time.Domestic air travel in America is widely available relatively cheap and popular.Airlines fear compentition from hight-speed rail and lobby against it.Travelling by cars is also popular.