The table provides information about opening year, kilometres of route and annual passengers of the underground railway systems in six nations. Overall, the underground railway systems’ date opened of surveyed countries was proportional to the kilometres of route, which was lower and lower through the time. Another key observation from the table is that Tokyo had the largest number of passengers per year travelling by underground railway, while the reverse was true with the figure of Kyoto.
The first underground railway system was operated in London, in 1863, which accounted for 394 kilometres of route. In 1900, Paris established the underground railway with only 200 kilometres, which was less than two times that of London. 155 kilometres of railway route was constructed in Tokyo in 1927, followed by the systems in Washington DC with less than 130 kilometres. Although the underground railway system in Los Angeles was erected latest, the distance that the train could travel increased by above 20 km with that built in Kyoto in 1981, which was the shortest railway route with less than 15 km.
Tokyo, while the opening time was significant far from now, it still was the top priority of many residents, with the largest number of annual passengers (1927 millions). About 1200 million people travel by underground railway in Paris per year, which stood at the second rank. Although having been constructed the earliest among 6 listed nations, the underground railway system in London accounted for only 775 passengers per year, which was less than nearly two times that of Tokyo. Washington DC and Los Angeles had only annually 144 and 50 million people travelling by their underground railway, respectively. Kyoto had the least prevalent underground railway system among 6 countries, with under 50 passengers per year.