Having the lowest car-ownership rate in the US probably helps Manhattan's overall numbers. :-) Per-capita square footage (which directly impacts heating/cooling

Having the lowest car-ownership rate in the US probably helps Manhattan's overall numbers. :-) Per-capita square footage (which directly impacts heating/cooling energy usage) is also fairly low by suburban standards, even in the rich parts of Manhattan. There are some big apartments on the Upper East Side, but most of them are still small compared to what you find in Westchester. I would definitely be interested in a more international version, too.