Interesting article on transportation costs

[BrianTH]

You can play with this tool to see a lot more about what their model is using as inputs and providing as outputs:

Housing and Transportation Affordability Index

If you set one of the maps to output estimated transportation costs, you can see what their model is outputting down to the Census block level. The lowest I found in scanning around was $430/month, and most of the City was more in the $500s or low $600s. As you head out into the suburbs, you eventually get up to the $800s and then $900s.

Are those numbers unreasonable? I don't know, but as an independent check, AAA publishes this estimate of car ownership costs:

http://www.aaaexchange.com/Assets/Files/200948913570.DrivingCosts2009.pdf (broken link)

They've got the average car driven 15,000 miles a year at an annual cost of $5,783. So a couple cars being used like that in your household, and you are getting into that $900 range ($963.83 per month, to be exact).

So I don't know all the details of their model, but it doesn't sound crazy to me. One thing I think is quite clear from the research is people often don't do a good job estimating their total transportation expenses, and they also overlook things like what a big difference it makes if you can change the number of cars in your household, and so forth.

In fact you can also set that map to show what their model is outputting for number of cars per household. Their model predicts a significant increase as you get farther out, and if their model of costs is anything like the AAA's, that is probably driving much, maybe most, of the estimated cost difference (meaning even more so than mileage).

In fact to fold this all together, I just spot-checked, and it looks like in the farther out areas the model is predicting the average is almost at 2 vehicles per household and pushing toward 30,000 vehicle miles per household. Meanwhile, in the cheapest City area I found before, their estimated average is 0.8 vehicles per household and under 7000 total miles. The City areas in the 500s or low 600s are showing vehicles per household between 1.1 and 1.3 or so, VMT around 7500-10000. I think all that is going to end up right in line with AAA's model.

[Bong477]

For this to work, you have to assume that (adjusted for income) people who live closer in are less likely to own cars. Is that really true? My wife and I would still own two cars no matter where in Pittsburgh we lived. People that can afford cars generally own cars, except in a handful of cities (Boston, NYC, etc) where owning a car just isn't practical mainly because there is no where to put it. If parking wasn't $500+ a month in NYC, a lot of people would own cars there too I think.

I agree that most people don't realize how expensive owning a car is though.

[BrianTH]

We'd have to look at how their model was built and the data they used, but I strongly suspect the average number of cars per household does observably decline with household mileage/centrality.

Part of that is pure economics: the less you use a second car the greater the expense per mile put on that second car, because there are fixed costs to car ownership. So the incentive to find a different way to supply those other miles is growing the less you use a second car. At a certain point as the costs per mile mount, some people going to start rearranging schedules, using public transport, using more cabs, and so forth. This is true even of people with decent incomes: they are still going to be sensitive to price at some level.

Now it is undoubtedly true that some couples in centrally-located/low-mileage scenarios still absolutely need two cars for some reason. On the other hand, for some couples that second car is just going to be a convenience, and as the costs per mile mount it becomes a less and less attractive convenience. The same goes for families with multiple cars: that third or fourth or fifth car might be a convenience, but not necessary.

And of course the closer in you live, the better your alternatives are likely to be. So put together the economics of decreased mileage and superior alternatives, and I have no doubt it is true the average cars per household does in fact decline as you move inward.

[BrianTH]

By the way, as I recall there is a fairly robust correlation between lower cars per household and greater public transit usage when looking at different cities. That isn't surprising, but it does imply better public transit options not only decrease car mileage, but also allow some households to eliminate some of their vehicles.

[Geeo]

One of the advantages we have of living in the city (Shadyside) is that my partner and I only need one car between us. Both of us are within a mile of work, so we don't even use it every day. For us, it's a lifestyle choice we've made, and we save a ton of money. I filled ol' Bess up two weeks ago and the tank is still 3/4 full. We walk a lot, and there are six bus routes and the East Busway station nearby. We can't imagine having to get in a car just to leave the house. Again, not everyone's cup of tea, but it's what we like.

[Bong477]

Aside from one oddball I know who rides his bike everywhere, there was a 1:1 person to car ratio for people I knew that could afford cars regardless of where they lived. I'm sure it goes down a little as you get more central due to people like Geeo and my oddball friend who can't possibly live in the suburbs, but I doubt it goes down from almost 2 cars per family to less than one car per household for the average household with comparable income.

I don't really understand the point of this study... you can save money on transportation by living closer to the city, not having a car, and walking or taking public transit? Duh. But then you don't have a car and you have to take the bus everywhere which for most people is unpaltable.

The assumptions seem obviously flawed to me if its conclusion is only 32% of Pittsburgh is "affordable" after accounting for transportation. How could that possibly be true? I took a peek at their website to try and understand where their numbers came from, but it wasn't obvious to me after a few minutes and I don't care enough to invest any more time than that.

[BrianTH]

Originally Posted by Bong477

Aside from one oddball I know who rides his bike everywhere, there was a 1:1 person to car ratio for people I knew that could afford cars regardless of where they lived. I'm sure it goes down a little as you get more central due to people like Geeo and my oddball friend who can't possibly live in the suburbs, but I doubt it goes down from almost 2 cars per family to less than one car per household for the average household with comparable income.

I guess I can't speak for who you know, but I know lots of couples who share one car. We were such a couple ourselves for a long time: when we first met we each had a car, then the battery ran out in one of our cars from disuse, and we didn't get around to jumping it for a month, and at that point we realized we didn't need a second car. So we sold one car and lived with one for a long time. Then we went back up to two when I was living in another city, and we have kept that going since I moved back. But our mechanic has started to tell us we aren't driving our cars enough, and recently the snow caused us to only use one car for a while, and then the other car had a dead battery . . . and now we are planning to go back to one car.

Never has this been an issue of income. But when the times you would both need to be driving separate cars are rare, and you aren't putting a lot of miles on in general, it really doesn't take an "oddball" attitude to just dump the second car.

I don't really understand the point of this study... you can save money on transportation by living closer to the city, not having a car, and walking or taking public transit? Duh.

I think part of the point is just to give buyers and policymakers a better idea of the numbers we are talking about, and how that relates to affordable housing issues.

But then you don't have a car and you have to take the bus everywhere which for most people is unpaltable.

Well, again a couple sharing one car is not exactly in that situation. Nor for that matter is a single person who lives near a Zipcar spot.

The assumptions seem obviously flawed to me if its conclusion is only 32% of Pittsburgh is "affordable" after accounting for transportation. How could that possibly be true?

That part of the study is about costs versus regional median incomes. I actually don't think this result is surprising at all: if you look around you can see lots of areas where there are very few below-median-income households. There are a lot of factors contributing to that fact, but one of them is that transportation costs contribute significantly to the costs of living in many areas, and people below the median income may not be able to afford them.

[BrianTH]

Oh, I meant to mention in many households in low-density areas the ratio can actually get above 1:1, meaning there are more cars than adult drivers. Now that may seem wasteful to some (or not), but the basic economic point I was making above holds in reverse: the more miles your household is putting on in total, the less the penalty for having more cars than you strictly speaking need.

[Bong477]

I didn't mean to imply anyone that doesn't own a car is an oddball... just that those in Pittsburgh that don't own one (by choice) are in the minority in my experience and certainly are not enough to drop the average below 1 car per household. Then again, maybe I have a warped view because I'm in the medical field and most of us work irregular, non 9-5, schedules that aren't really conducive to commuting via public transit. Perhaps there are a lot of families/people with 0-1 cars I don't know about...

[BrianTH]

Originally Posted by Bong477

I didn't mean to imply anyone that doesn't own a car is an oddball... just that those in Pittsburgh that don't own one (by choice) are in the minority in my experience and certainly are not enough to drop the average below 1 car per household.

Something just over 1 car per household was the norm in most of the City, and again I think that is consistent with lots of couples/families sharing a car. The place I noted that slipped just under 1 per household was the Lower Hill, and there you are within walking distance of Downtown.

The big difference was really just going from close to 1 car per household in the City to around 2 cars per household in the suburbs. Combined with the added mileage, you are talking about an average additional cost of around $300-400 more a month, give or take. That is indeed a big chunk of after-tax income for people around the median income.

Then again, maybe I have a warped view because I'm in the medical field and most of us work irregular, non 9-5, schedules that aren't really conducive to commuting via public transit.

Yeah, obviously public transit doesn't work for everyone. But we know around half of the people working in Downtown aren't using cars for their commute, and Oakland has a lot of non-car-commute workers too. And of course a decent number of households only have one working member (either it is a single, or a couple with a non-worker), and some working couples carpool, and so on. Average all that with the households that do need two cars, and I don't think it is surprising you would see numbers like 1.1 or 1.3 in many close-in neighborhoods.