underground systems passengers rate
The table provides a statistic about total length and number of passengers per year for 6 underground systems in 6 cities around the world. It is arranged of year opened ascending. Generally, the older underground systems were opened the more longer underground systems's route are. Additionally, people have the usual trend in use subway in Early modern period. In modern period, this volume fall dramatically.
As can be seen from the table, it is easy to realise that the information in the table is divided into two groups. The first group includes London, Paris and Tokyo which are an oldest underground systems. But, these underground systems were built with the length longer than the other three. Moreover, the numbe of passengers per year of the first group is bigger than the rest. Perhaps in the early modern period, means of individual transport is not popular. By contrast, modernization as a cause of crisis of individual transport. That's why the number of passengers per year for underground systems in Washington DC, Kyoto and Los Angeles significant smaller than old systems.