Maintaining 30 mph in a dense city, such as downtown SF is probably high (although then enough time is spent idling that my costs-per-mile estimate becomes too

Maintaining 30 mph in a dense city, such as downtown SF is probably high (although then enough time is spent idling that my costs-per-mile estimate becomes too low). Fair point. I pulled the 30 mph out of someone else's guess in the AMA article mentioned, and from the most recent Lyft report I read, saying it wasn't uncommon to drive to the airport (removing the Mustache first, of course) during which time 30mph is low, and the time-between-rides becomes high.