Alex Tabarrok linked to this detailed deck from Alon Levy picking apart the possible reasoning for why NYC subway construction is so much more than other urban centers around the world.

Levy is to be lauded for his pioneering work on this issue yet isn’t it weird that a Patreon supported blogger has done the best work on comparative construction costs mostly using data from newspapers and trade publications? New York plans to spend billions on railway and subway expansion. If better research could cut construction costs by 1%, it would be worth spending tens of millions on that research. So why doesn’t the MTA embed accountants with every major project in the world and get to the bottom of this cost disease?

Levy’s detailed dataset is here. See also this Josh Barro piece on infrastructure costs, and Patrick Collison’s archive of quickly-completed construction projects for counterpoints to the slowness problem.