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Peak Car: not just the economy

There’s a long running debate over whether the flattening/decline of traffic growth over the past few years is attributable mainly to the rather ‘up and down’ economic situation over a fairly similar time period – or whether this reflects a more fundamental change in travel habits.

This is a critical question – on the one hand if the recent trends are due to the economic situation (certainly the position taken by NZIER economist John Stephenson at the transport conference I went to a few weeks back) then they’re just something of an anomaly and likely to ‘correct’ over time back to normal steady traffic growth. Under this scenario, the long term transport models we have that predict significant traffic growth in the future might be right and there may be some long term justification for many of the motorway we’re either building or planning at the moment (even if we’re perhaps building them too early compared to other transport priorities).

On the other hand, if the flattening or decline of traffic volumes is more independent of the economic situation then it may be a sign of longer term changes to travel habits. These longer term shifts potentially arise from changes such as a fundamental increase in the price of petrol, technological advances which mean that cars aren’t needed to interact with friends in the way they once were, urban structure changes which reflect a ‘re-urbanisation’, improved public transport and so on. The key point here is that these changes are likely to be fairly long-lived – fundamentally impacting upon future predicted travel growth, completely debunking transport models and having an absolutely massive impact on future transport needs.

A new study from the US PIRG institute looks at this question in a bit more detail – to try and understand in more detail the changing travel patterns across the USA over the past few years. Some key headline findings outline in the report include:

  • The proportion of workers commuting by private vehicle—either alone or in a carpool—declined in 99 out of 100 of America’s most populous urbanized areas between 2000 and the 2007-2011 period averaged in U.S. Census data. (New Orleans was the only exception here).
  • From 2006 to 2011, the average number of miles driven per resident fell in almost three-quarters of America’s largest urbanized areas for which up-to-date and accurate Federal Highway Administration data are available (54 out of 74 urban areas).
  • The proportion of households without cars increased in 84 out of the 100 largest urbanized areas from 2006 to 2011. The proportion of households with two cars or more cars decreased in 86 out of the 100 of these areas during that period.
  • The proportion of residents bicycling to work increased in 85 out of 100 of America’s largest urbanized areas between 2000 and 2007-2011.
  • The number of passenger-miles traveled per capita on transit increased in 60 out of 98 of America’s large urbanized areas whose trends could be analyzed between 2005 and 2010.

Perhaps the most interesting findings from the report arise when the economic performance of different cities over the past few years is compared with the average number of vehicle miles driven per person. You might expect that cities which have struggle economically over the past few years would have the biggest decline in per capita travel – because of higher unemployment, reduced business travel, generally less wealth to spend on cars etc. However, the report’s analysis actually shows the opposite is true:

traffic-economic-performance-uspirgWhat the data appears to be showing is that cities which experienced the greatest decrease in per capita VMT between 2006 and 2011 were the cities which fared best in terms of lower unemployment, higher median income and a lower level of increase in poverty.

The report’s authors make some pretty heavy hitting conclusions and recommendations for policymakers:

The study found that cities with the largest decreases in driving were not those hit hardest by the recession. On the contrary, the economies of urbanized areas with the largest declines in driving appear to have been less affected by the recession according to unemployment, income and poverty indicators.

“Government should support transportation initiatives that reflect these travel trends,” said Baxandall. “Instead of wasting taxpayer dollars continuing to enlarge our grandfather’s Interstate Highway System, we should invest in the kinds of transportation options that the public increasingly favors.”

I’m guessing that if someone were to study what is happening with the economy locally we would see some similar trends. Meanwhile Auckland continues to gear up for a giant spend-up on motorways.

30 comments to Peak Car: not just the economy

  • The big question with regard to those US figures is what will happen from now on,
    One of the biggest drivers of car use in the US is jobs and job security,( especially for any decision to buy a new car)

    The US has just gone through a once in a generation recession and has still not got back to the number of jobs it had before the recession , see this chart from Calculated Risk

    Such an event is very noisy from a trend point of view, so comparing data points within this recession to those before it is definitely risky from a robustness POV, Additionally the use of the year 2000 makes robustness even more worrisome,
    the US was at the height of the .com boom with unemployment at 4%,

    It would certainly seem logical for household’s in a recession to attempt to lower costs by shifting from Car use to lower cost PT,

    The big question is what will happen once the actually recovers, Will people continue using PT or go back to car travel?

    Then there is the whole baby boomer retiring Demographic issue, although for the US that is much less of an issue than it will be in places like the EU…

    peak car and commuting may have happened, but it is just too noisy in my book to say so.

    • Greenie the driving stats discontinuity preceded the downturn. Anyway the change is now 8 years old and showing every sign of being structural. There is no law that says after a major recession the world will go back to exactly as it was. Also did you not read the above?: There is a correlation between the best performing urban economies and LOWER driving figures. How can this be? Increased urbanisation, which is also consistent over this period is tightly correlated to less driving, both fewer trips and shorter journeys. Also it is hardly inconceivable that people who drive less to save money may stick with that change even if their financial circumstances improve. Especially once if the structures to support this lifestyle change improve over the period, which they certainly have in many US and European Metros, and is coming to Auckland.

      Which area in NZ had the biggest population growth between the last two census: Auckland City Centre up 46.5%… those people will just not drive as much as when they used to live in the ‘burbs or beyond.

      I’ve been calling this for years and see no reason not to keep calling it, and those that can’t imagine change like our government and an economist I heard recently with an elaborate way of persuading himself that the 1970s are about to return any moment are being proven wrong everyday.

      Change does happen, and structural change happens often enough and is usually accompanied by economic upheavals [and plenty who can't recognise it]. The fact of the recession does not disprove the nature of the change but rather underlines its seriousness.

      There’s an awful lot of wishful thinking in the ‘business as usual’ set.

      • tuktuk

        ‘There’s an awful lot of wishful thinking in the ‘business as usual’ set.’

        A lot more than wishful thinking is going on there in the ‘business as usual set’. There is in fact a full blown King Canute type effort being made to avert the incoming tide with one last massive round of road-building. The trouble is that the billions being spent, means that reversing the government’s policies are going to be very difficult if we are deeply indebted to the road builders. No doubt similarly minded Crosby-Textor advised Anglo-saxon governments around the western world are attempting the same thing – that includes various parts of the US (we only get the good news stories on this site), and now Australia.
        Next year’s election is shaping up as one of the most important in New Zealand’s history.

        • Yes. There is a generally accepted idea that Transport policies are of no consequence at elections in NZ. I think this too may be changing. Next year’s one might just see the return of this as a relevant issue, partly because it is intimately wound up in housing affordability but also because of National’s aggressive backwards leap in this area has forced a wedge in policy between the two larger parties. It all comes to a head nicely in the East/West issue. A lot of trouble for National if they persist with the more destructive versions there. Interesting.

      • Kent Lundberg

        The following higher order factors are influencing the stats:

        -people are moving to cities
        -people generally prefer city centres, walkable neighbourhoods and the advantages of proximity -
        -millennials increasingly choose urban lifestyles.
        -business are moving back to the city-

        You can argue about the details, eg unemployment, petrol prices, but the big shift is structural, and the result will be a continual decline of VKT. This trend is also self-reinforcing in a sort of virtuous cycle.

  • Dave B

    Yet more confirmation of what we are increasingly coming to see as reality.
    Unfortunately this is exactly what our government and its motoring-enthusiast supporters don’t wany to hear, and on current track-record, will refuse to listen to at any cost. The imperative to change the government next year remains as strong as ever, if we wish to avoid possibly the grossest misallocation of economic resources in the country’s history. (At least Muldoon’s “Think Big” projects were designed to lessen our dependence on imported oil. Key/Joyce/Brownlee’s “Think Big Roads” will worsen it).

  • PeterH

    Parts of US like Detroit still believe grow comes from investing in more freeway.
    I-94 Expansion: Controversial SEMCOG Vote Passes, Will Widen Freeway Through Detroit

  • SF Lauren

    Of course in order to gain anything from this we need to look at what the drivers were behind this shift.

    For instance the first few numbers you quote are all largely driven by policy rather than maintainig the status quo and a change happening regardless. For instance, if we build something like the northern busway, like we did in 2008, you would expect more people to take the bus in the future. Similar to if you build a train station in the middle of town, like we did in 2003, you would expect more people to take the train.

    • Dave B

      Well if it is transport policy which has brought this shift about (e.g. as it has with the Northern Busway), then it gives the lie to the oft-repeated claim that Aucklanders have such a love affair with their cars that you’d never get them to use P.T.

      And it also supports in retrospect, the theory that Aucklanders did not “choose” to lose their formerly good public transport in the 1950′s, but had it progressively taken from them by transport policy which increasingly robbed them of choice.

      So now, whether by choice, policy, or a bit of both, are we starting to see a reversal of the inexorable drift towards car-dependency which has blighted Auckland for so long? Let’s hope so!

  • George D

    Driving from my house to work is about 5 minutes faster than the train, door to door. It’s also about the same price. But nine times out of ten* I regret driving, because I’ve lost half an hour of productivity or recreation.

    We are a smartphone generation. This has only happened in the last 5 years, but culture shifts quickly.

    *The tenth time, I sit near a group of noisy teenage boys.

  • Iiq374

    George D you obviously either
    A) don’t catch the Southern line or
    B) exclude the train never arriving from your ‘days you catch the train’

    Over 2 weeks had 4 trains cancelled and now stuck on another one going no where without even AC. And that’s ignoring the one that was cancelled because it killed someone.
    Auckland Transport is currently putting a whole lot of people back in their cars.
    I cannot believe you think spending so much on the CRL when there is such a crap operation in charge can possibly be a good investment for rate payers.

    Auckland Transport – it’s faster to walk

    • Dave B

      Well if Wellington is anything to go by (with its excellent new “Matangi” trains), then Auckland should also notice a step-change in train reliability once the CAF electric units come on stream.

      • iiq374

        Apparently the reason for my being 2 hours late tonight was the driver running a red light. Electric trains going to help that too?

        • Dave B

          No, but they will have automated control systems which closely supervise what the driver is doing, clearly advise him of what he should be doing, and intervene if necessary.

  • Iiq374

    And still on the train in the same spot. Awesome job AT.

  • Kent Lundberg

    On my way home tonight I was riding my bike faster than the cars queued on Bond Street. In one out of three cars the driver was actively messing with their phone.

  • Gas Gusler

    US gasoline consumption is pretty much the same today as it was in year 2000. I don’t know where this report is getting its stats from but it doesn’t sound very accurate to me. People do not buy petrol for any other reason than driving cars (unless you think there was a grass cutting boom in the US). The USA consumed 3’100’774 thousand bbls in 2000 and 3’177’687 thousand bbls in 2012 (the most recent full year data obviously). The peak consumption was 2007 at 3’389’269 thousand bbls and its pretty obvious why there was a decline after that. The trend flattened last year and 2013 consumption is to date up 1% on last year.
    The US Government invested a lot of money in the Auto industry to keep jobs and encouraged the public to buy new cars. These new cars are more fuel efficient than the older fleet so it is logical to conclude that in the USA people are driving more miles. US new car sales totaled 14.5 million in 2012 and are on track for around 15.8 million this year.
    Here is a link to the EIA data on US gasoline consumption

    • Tom

      So, by your numbers the yearly growth in US petrol consumption was 0.2%. In the same period, average US population growth was ~0.9%.

      According to EIA ( the yearly efficiency increases in the last 15 years are 0.5% for cars and virtually nothing for SUVs, trucks and heavy trucks. In average, the US car fleet is 0.26% more efficient every year.

      The numbers don’t really match up with your claim.

    • John Polkinghorne

      Phil, car sales are now increasing, yes, as the US (slowly) recovers from the recession. They remain well below peak levels, in the US, New Zealand, and I imagine most developed countries.
      We’ve published other graphs in the past which show that vehicle travel has dropped off in the US, certainly on a per capita basis, and I believe on an aggregate basis too.

  • Gas Gusler

    Tom, The US fleet has been renewed in the last few years thanks to a huge bailout by the US Govt. Why would you use statistics over 15 years when the real change has been since 2008? You might want to read the Consumer Federation of America report on changing fuel consumption.
    If you cant be bothered, here are the points you need to consider:

    “Comparing popular 2009 models with 2013 models, the Consumer Federation analysis shows that the percentage of vehicles getting at least 30 mpg rose from four to 12 percent”.

    “Over the same time period, the percentage of popular vehicles getting at least 23 mpg rose from 30 to 56 percent; and the percentage getting under 22 mpg fell from 70 to 44 percent.”

    So the EIA data shows the US petrol consumption is increasing in total gallons sold while at the same time the CFA data shows the US fleet is becoming more fuel efficient. That dear boy shows without any doubt that our American friends are driving their cars more this year than last and more importantly that the investment in roads (in the US) continues to be money wisely spent.

    • John Polkinghorne

      As it happens, Phil, I have studied these kinds of reports in quite some detail. For starters, the report you link to is only analysing trends in new cars. It takes many years for those trends to make a noticeable impact on fleet-wide consumption. Especially when new car sales have dropped significantly, as they did in the US recession.

      Secondly, the changes have been partly driven by some long-overdue legislative changes in the US – tightening CAFE standards for the first time since the early 80s, and requiring car manufacturers to sell, on average, more efficient cars. Of course, that’s also something which consumers have been looking for, since gasoline prices have doubled in the last decade in the US, and are currently at their highest price ever in real terms (see

      Thirdly, “real world” fuel efficiency hasn’t really budged, because cars make more use of energy-intensive appliances like air conditioning, and cars have spent more time stuck in traffic. I go through some of these trends at

  • MoT data [they may be hopeless at seeing change coming but they are dutiful at counting what has already happened]:

    NZ Light Petrol Fleet Mean Fuel Consumption:

    year l/100km
    2001 10.11
    2002 10.10
    2003 10.17
    2004 10.37
    2005 10.09
    2006 10.25
    2007 10.32
    2008 10.24
    2009 10.13
    2010 10.16

    There you go. Sure some new cars are more fuel efficient, especially small ones and some hybrids. But that ain’t what’s on the road in practice. And it’s clear that many take more fuel efficiency as a justification to buy a bigger lump of tin to drag around….. So it goes.

    Luckily many of us just aren’t driving so much anymore. This is a trend that will have more influence on oil dependency, money wasted on vast highways, and urban quality, than incremental engine efficiency improvements…. still cling to your old world view Phil it makes for a good laugh: Man stuck in 20th Century fails to comprehend change; you’re not alone.

  • John Polkinghorne

    It seems like the MoT never got around to putting in the 2012 figure, but the 2011 figure also shows very little budging. Bet you five bucks 2012 is more of the same.
    Phil, media reports often focus on very short term data – this year vs. last year, say. There are very few graphs that show trends over a 10 year period, for example. Fortunately, we do do that sort of thing. See this, for example.

  • Richard29

    Has anybody done work graphing different degrees of population density and car use/ownership. A binary Urban/Rural split doesn’t really adequately cover the different scenarios. I would think car usage and ownership is lower in urban downtown Auckland than urban downtown Dunedin or suburban Auckland. I would think urban downtown Manhatten or downtown Hong Kong would have extremely low levels of car ownership.

  • I’ve always had a feeling that fossil fuel dependency is what keeps stopping economic recovery – when the economic ball starts to roll again, petrol pump prices go up pretty sharply, and said economic ball deflates and stops.

    To me, those stats seem to align with this – to me they suggest that cities less dependent on oil for transport (with the private car being the most inefficient user) are consequently less susceptible to oil price induced economic hardship.

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