The given chart demonstrates: opening date, kilometers of route and passengers per year of Underground Railway Systems in six megalopolises (London, Paris, Tokyo, Washington DC, Kyoto and Los Angeles).
To begin with, the youngest system was built in Los Angeles in the millenium (2001 year). It has 28 kilometers of route and 50 million passengers per year. The longest Railway System (394 kilometers of route) was built approximately 130 years before (in 1863), and carries 775 million passengers during one year. The most demanded systemswas built in Tokyo and Paris, they carry 1191 and 1927 million passengers per year respectively. To compare Kyoto (1981) and Washington DC (1976) Railway Systems, the number of passengers in the first city 3 times less than in the second one, 45 and 144 million passengers per year correspondently. While difference between lenght is 115 kilometers (11 and 126 kilometers respectively).
To sum up, the oldest Railway systems built in London, Paris and Tokyo are highly demanded, while youngest ones are not so popular.