Manhattan, at least, hasn't really had an increase in housing supply. The population is actually lower today than it was in the post-WW2 era (down ~20%, from ju

Manhattan, at least, hasn't really had an increase in housing supply. The population is actually lower today than it was in the post-WW2 era (down ~20%, from just under 2 million then, to around 1.6 million today). Some of that is because of changing demographics (e.g. apartments that once held 4-person families now holding a 2-person couple), but the housing-supply constraint has been a pretty hard cap on population. There has been a lot of construction, but it's gone into mainly: 1) expanding commercial real-estate; and 2) replacing older, smaller residential units with newer, bigger ones. Redevelopment of the 2nd variety sometimes even reduces the number of housing units (but each unit is nicer).