I’ve been arguing for a long time that the “commuting calculators” pushed by cyclists to convince people to ride their bike to work are skewed, since they assume that you can effectively divide the total cost of owning a car by the number of days in a year, then get credit for each of those days you leave it in the garage.
Capital Metro’s example, for instance, assumes depreciation as one of the costs you save. (To be fair, they have now allowed you to zero out this field, which is quite a concession for them). I’d argue it should be zero or at least very low, since most of the cost of depreciation is a function of time, not miles. I’ve previously argued that a more rational accounting of costs shows that it’s unlikely that a large number of suburban commuters would begin using the bus to get to work due simply to the cost of gasoline (which is why we need a real urban rail system that provides a time incentive to use transit; not this Austin-screwing transit-killer foisted on us by Mike Krusee).
Now the Washington Post has done an analysis which, although it still includes depreciation, correctly mentions other fixed costs which don’t go away. In DC, as it turns out, you might not save anything by leaving your car in your driveway. Whatever you think of the merits of subsidizing public transportation, surely even the most reactionary of road warriors would admit that something’s wrong there.
What could be done to help fix this problem? One obvious answer is to pay for all of the costs of road use through the gasoline tax, instead of through a variety of non-user-fees as we do today (property and sales tax especially). The suburban regions of DC, like Texas, pay for a lot of their roads this way – meaning that you pay the same (hundreds to thousands of dollars a year) whether you drive 100, 10, or 0 miles a day. Anything which increases the variable cost of driving while leaving the fixed cost alone (or even decreasing it) can only help people make more efficient decisions about how to travel on each trip. Another obvious answer would be forcing insurance companies to deliver on mileage-based insurance (and, no, despite publicity, they really aren’t doing this today – or I’d be jumping all over it).