When comparing two cities, it is relevant that they be of similar in size, and perhaps economy.
Comparing Paris transport and Vancouver transport is rather unrealistic, Paris being so much larger, with a large, very developed system, (in a city of 9,000,000+ )
SO ... we take a look at two rather similar cities: Vancouver and Brisbane. Both have similar metro populations, and share other features, such as the dense downtown.
Brisbane has an extensive rail system, Vancouver has Skytrain. If interested
please read the links below and compare stats. The results are often a little contradictory.
A Brisbane overview .....
http://en.wikipedia.org/wiki/Brisbane#Transport
Then more specific ....
http://en.wikipedia.org/wiki/Transport_in_Brisbane
A nice little map
A closer-up view of the Brisbane Citytrain network
http://en.wikipedia.org/wiki/Queensl...l_City_Network
check pax numbers .....
then look at the figures for skytrain
http://en.wikipedia.org/wiki/SkyTrain_%28Vancouver%29
the lesson here? It seems Vancouver moves more pax with fewer lines, using a grade seperated system, (not even finished yet).
I guess it mostly boils down to low-density suburban sprawl, and the manner needed to serve it. And of course we have Vancouverism. Brisbane, apparently, does not.