This article looks at car sharing, attempting to figure out how many cars are removed from our streets, and what the impact on VMT is.
The consensus is 9-13 cars per sharing vehicle (compared to claims of up to 32 cars).
But the really interesting finding is that there is substantial VMT reduction even though many car-sharing customers are from car-free households. The conclusion is that over time you learn how to use the car less and less, as you get better and better at using other modes.
But the studies by Shaheen and other researchers show that VMT among carsharing customers drops in subsequent years, often quite dramatically, as people figure out that it’s not really so hard to get around by public transit, bike, or on foot. “When people use carsharing, they use it less and less and less,” Shaheen told us.
That matches my personal, anecdotal experience. I think a big part of that is because when each car-share trip becomes an incremental expense, the pricing signals encourage you to think harder about the alternatives.