You miss the point -- it's not about the number -- it's about the change since 1937. No where in the reference you provide is there any evidence that this number has grown since 1937.
From the Apr 10th NY Post: "More than 1.65 billion straphangers used the system in 2012 — numbers that haven’t been seen since 1946 when ridership was more than 2 billion, according to MTA statistics released yesterday"
Has the relative income of the residents changed since then? I.e. if the average income in 1937 was on par with the national average and now its 200x that, perhaps there's greater demand for a luxury service such as cabs from a greater slice of the population.
http://www.nypost.com/p/news/local/subways_on_roll_fDYxgwu92...
From the Apr 10th NY Post: "More than 1.65 billion straphangers used the system in 2012 — numbers that haven’t been seen since 1946 when ridership was more than 2 billion, according to MTA statistics released yesterday"