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How census mode share has changed over time

On Saturday we finally saw the first glimpses of information on the Journey to Work (JTW) data from the 2013 Census for Auckland (we received the national figures a few months ago). This morning Stu looked at how effective investment in each mode has been since 2006. For this post I’m going to look at how the trends in Auckland have been changing over time and I’ve managed to find the data from as far back as 1996.

First up we have the total number of people in each category.

2013 - Auckland Journey to Work - Total Chart

One thing that surprises me about this figure is just how little the “Worked from home” figure has changed over time. As a percentage of the total it has remained unchanged at 7% despite great advances in the ease and ability of people to work at home. It also defies the claims of those who argue we don’t need to invest in PT because more and more people will work from home in the future and not need to travel.

I’ve also simplified that by looking only at the modes that required transport and grouping similar ones together. I have included the “Other” column with PT as I understand much of patronage in that bucket is related to the ferries. You’ll also notice that I’ve dropped the “Working from home” and “Didn’t go to work” columns to only look at those who are going to work.

2013 - Auckland Journey to Work - Chart Simplified

So all modes had an increase but the fascinating thing is that there was a larger increase in PT than there was in Private Vehicles. Converting the figures above to mode share percentages we get.

2013 - Auckland Journey to Work - Percentage

and the simplified version

2013 - Auckland Journey to Work - Percentage simplifed

Private vehicles clearly still dominate the figures for how people get to work although that is slowly starting to change as more people use public transport, walking and cycling as those options improve. During the last census cycle we’ve had big improvements to the rail network and the construction of the Northern Busway, both of which have driven a lot of growth. By the next census AT should have completed the current tranche of projects that will really revolutionise PT in Auckland. These include Electrification, the New Network, integrated ticketing/fares and other customer experience improvements. Combined those improvements could quite possibly push private vehicle usage below 80%.

Further if the current trends continue then from these numbers we might be able to say that 2001 (or sometime around then) was the point when car dominance peaked in Auckland. Imagine just how much further that share would drop if we were to build the Congestion Free Network.

Lastly just to try and put the changes in perspective. What would have happened if the growth that occurred had of been at the same mode share percentage as 2006. By my calculation it would have meant we would have had just over 11,300 more private vehicle trips, 9,000 less PT trips and 2,300 less active trips. Most of the growth of active and PT trips has been to the city centre and so to accommodate those extra 11,300 private vehicles trips on the road network would have needed 2-3 extra lanes of road capacity, in other words effectively we would have needed another motorway to the city centre.

37 comments to How census mode share has changed over time

  • nonsense

    I wouldn’t put cars and motorcycles in the same group. I see it more in the “active” transport category, and needs very different thinking than car transport

    • Steve D

      Other than parking, how are motorbikes different from cars? They go at the same speed and use lanes the same way. They’ve certainly got nothing to do with either walking or cycling, the actual “active” transport.

      • Certainly there is a difference between electric bikes and motorbikes, the former being much closer to peddle only bikes.

      • nonsense

        they go at different speeds, use lanes differently and can actually use different lanes like bus lanes get killed and blamed like cyclists do. Lots of things in common.

        • Steve D

          If full-size motorbikes are going at a different speed to cars, or using lanes differently that’s generally because they are speeding or illegally overtaking (“lane splitting”, for example). The only real exception would be learner motorcyclists who have a 70km/h limit – this is only an issue on the open road. But that’s hardly unique to motorcycles: highways have slow drivers, trucks, buses, tractors, livestock, cyclists, and even the occasional pedestrian.

          There’s also mopeds and the like, which are sometimes too slow to keep up in city traffic, but I think we should have a long hard think about whether it’s a good idea to have the special 50cc category at all. They have many of the same dangers as more powerful scooters and motorbikes, and I think it’d be beneficial to require a motorcycle licence for them. Which in practice would pretty much kill off the 50cc for good – you’d be able to buy a larger scooter with the same licence. 50cc scooters also tend to be two-stroke, which is bad for (non-carbon) emissions, as well.

          There’s lots of subtle ways that roads can be designed to be more friendly to motorcyclists (e.g. avoiding wire barriers), but in terms of broader transport planning, motorbikes will always be sharing normal road lanes with cars. Petrol scooters, let alone motorbikes, don’t mix with cyclists – the only niche there is electric bikes, which should still be limited to cycling-like speeds if they’re going to use cycle lanes.

          • nonsense

            lane splitting is legal. The rest is just the typical car driver view on motorbikes

          • Steve D

            Lane splitting is generally illegal: you have to drive fully within a lane, and you cannot pass on the left within a lane. The only time lane splitting would be legal is if you are entirely within a single lane, and passing on the right.

            See http://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=10688399 and read the law

            http://www.legislation.govt.nz/regulation/public/2004/0427/latest/DLM303043.html
            http://www.legislation.govt.nz/regulation/public/2004/0427/latest/DLM303050.html

            Sure, there’s differences between motorbikes and cars. But which differences are relevant to transport policy? It’s certainly a bad idea to even think about mixing motorbikes and bicycles, let alone motorcycles and pedestrians.

          • nonsense

            see, that’s the problem, road rules are made for cars forgetting other users. Lanesplitting on a motorbike is safe but it’s illegal in some cases because the legislator only thought about cars. Same as a cyclist crossing with the pedestrian phase. It’s not the same as if a car was crossing with the pedestrians, is it? Cars not only get the most investment, they also get favourable laws with it. I would like to see a “cars always give way to PT busses taking off from a stop” law as in other countries. It’s not only money, it’s also attitudes and old school stereotypes that move the balance in favour of cars, and still their use is declining. I never said to physically mix motorcycles and pedestrians, but to start thinking at motorbikes as another part of the transport environment with different needs than cars. Very little needs actually, and a lot of gain.

          • Steve D

            > I never said to physically mix motorcycles and pedestrians

            Point taken. I was responding to what you first said – you wanted people to think of motorcycles as part of “active” transport, which traditionally means walking and cycling, and similar things like wheelchairs and low-end mobility scooters.

            But motorcycles aren’t slow the way bikes and pedestrians are. They may pose little danger to well-armoured car drivers, but they’re just as dangerous for each other, let alone cyclists and pedestrians. They’re also more vulnerable than cars – but since they’re easily able to keep up with car traffic, that’s not nearly so critical. Motorcyclists don’t generally have to worry about being overtaken too close.

            > start thinking at motorbikes as another part of the transport environment with different needs than cars
            > Very little needs actually, and a lot of gain.

            Yes, but what does that actually mean in practice? What do you want to see done differently?

            There’s an infinite array of possible vehicles we could cater for in some way. I guess I don’t see the case for encouraging motorcycling, in particular – rather than treating it the way we treat, say, horse riding – making it as safe as possible on shared roads, without expecting it to play a major role.

            The case for encouraging cycling is very particular – it opens a new option to people that existing methods don’t really meet. Walking’s too slow, in a suburban-scale city. PT doesn’t serve point-to-point trips well. Driving is dangerous, polluting, expensive, only open to a subset of the population, and uses up a lot of real estate. Cycling is cheap, fast, and personal, and fills a huge niche. In countries that really provide for it, it’s the mode of choice for 10%, 20%, 30% of trips. In Amsterdam it’s the mode for nearly if not more than half of trips. It opens up new options for children, teenagers, students, adults without driver’s licences, and the less well off. It avoids the environmental issues with cars and (to a lesser extent) public transport.

            What does motorcycling bring to the table? It’s even more dangerous and nearly as expensive and polluting as driving. Motorcycles have atrocious noise quality (there’s generally zero attempt to install a decent muffler – the noise is seen as part of the fun). There are cheaper forms (the 50cc scooter), but they exact a huge cost on air quality. Motorcycling offers nothing for kids, or adults with no driver’s licences, or people with limited or no parking at home. At present it mostly provides a “funner” option for trips that would otherwise be made in a single-occupant car. What would make it useful to anyone else?

            As for the safety of lane-splitting: there’s not a lot of hard evidence one way or the other. But there’s some very obvious potential safety hazards, similarly to filtering on a bike. It’s fine as long as the cars are moving slowly: but you end up with significant conflict merging again when the cars start to move. You’d expect that to cause problems, and plenty of US jurisdictions have explicitly chosen to ban lane-splitting, rather than “because the legislator only thought about cars”. Far more than have chosen to legalise it (that is, none).

        • TheBigWheel

          In Holland, motor-scooters even use bike lanes. Maybe they could here too? With appropriate constraints.. I’ve had a few near misses as a pedestrian with scooters haring around the bike lanes much faster than (average Dutch) cyclists. Presumably the same risks apply to e-bikes. That said, in the big picture, it’s better to have fewer cars.. and to segregate bikes, and e-bikes.. and scooters.

          • It seems this is a problem in the Netherlands so best not to import it here:
            http://bicycledutch.wordpress.com/2013/02/23/the-moped-menace-in-the-netherlands/

            Electric bikes are a different matter. They are legally restricted to 300W and shouldnt be going faster than 25km/h. I see in the Netherlands there is actually a law restricting speed to 25km/h and I support the same on cycle/shared paths here. As between cars and cycles, we have to look after the more vulnerable group – in this case the pedestrians.

            Electric motors can produce very fast speeds on such a light vehicle and with terrific torque – ebikes have the potential to be very fast if the law isnt observed. But then so does every other type of powered vehicle.

  • Fred

    All the trends now heading the right way.

    – Car modeshare declining quite dramatically.
    – PT modeshare jumping up with bus turning around its 01-06 decline.
    – Cycling turning around previous declines.
    – Walking continuing to grow.

    Lots of great news there.

  • Greg N

    Or to look at the figures another way.
    If using 1996 as the base year (17 years elapsed), then since then, the following growth in each mode has been: Private vehicle: 29%, Active mode: 37.34% and the true star – PT: 59.97%

    Showing that when you build PT they will use it.

    Also note that Private vehicle growth has dramatically slowed since last Census (7 years ago), to be only 10,200 higher – or a 2.4% increase over 2006.
    The real growth in private cars was between 2001 and 2006.

    So I don’t think we can say the “Car” rot as mode showing largest growth set in from 2001 (As it did for mode share), more like from 2006.
    And in fact the 2013 census was the first one since 1996 (and possibly earlier) to show that the Private vehicle mode no longer lead the growth figures like it did in 2006 and 2001 – PT took that crown in 2013.

    • TheBigWheel

      Good analysis..

      Interesting looking at the share of growth 2006-2013:

      1. PT 44% ..largest single share!!

      2. Car 41%

      3. Active 15% …think about it.. 15% of all growth, with a base of 6.3% !!

      • TheBigWheel

        Or even simpler..

        1. PT & active 59% of growth

        2. Car 41 %

        This is how Aucklanders are choosing to go to work.. even with today’s extreme mono-modal infrastructure. This is what the investment for new infrastructure should reflect.. to Stu’s post below.

  • JohnP

    Or to look at it in yet another way. I plotted the data in your second table and used ordinary least squares regression (using 1996 as year zero). The regression coefficients I got are Y(private)=338,811+6327X and Y(pt)=30,166+1164X where X is the number of years. The slope for private vehicle growth is five times the slope for PT so the lines diverge!. The only way you can model PT reducing the dominance of private vehicles is if you ignore the first two data points (the 1996 and 2001 data), then you get convergence. So it all comes down to whether you think the car trend has changed.

    I noticed that the median income data for Auckland showed $26,800 for 2006 and $29,600 for 2013 (or $24,835 deflated to 2006 prices). Perhaps the drop in real median income is the driver in these trends

    • lefty

      I don’t think a linear model on the natural scale makes any sense though, right? I mean you’re saying that ALL transport options are decreasing in terms of per-capita usage in that case, as clearly population size is exponential. Further, the model is dominated by the large numbers in the car category on the log scale, so it’s not surprising that the slope is so much larger, as you’d expect increases to be somewhat proportional to the starting values (i.e. exponential). Further, using separate models means each one has 4 data points and 3 parameters to estimate, i.e. 1 degree of freedom.

      Thus, modelling on a log scale makes more sense. When you do so, you get no significant difference between the growth of cars, other, bus, motorbike, or walk, though the coefficient for all of these with respect to cars (baseline) is positive, indicating they’re going up faster. Trains are growing significantly faster (coefficient 0.076/year, P < 0.001), suggesting growth 8% faster than the growth of car usage.

      Model code here: http://pastebin.com/Fe7i0vDn

      Model output here: http://pastebin.com/STvvnLXq

      • lefty

        In case anyone’s interested, model fits are graphed here:

        http://imgur.com/tcCp27f

        Code: http://pastebin.com/vMFe6KL2

      • JohnP

        Hi Lefty. The modes need to sum to the total work trips which are not increasing exponentially so I wondered if the participation rate is dropping. Total work trips seem to be declining per capita. When I checked population data I noticed we lost 16,000 people from the reported 2006 census to the 2006 data reported in the 2013 census. It must have been new boundaries. So we are not comparing like with like. Which ever you use for 2006 still doesnt give an exponential regional population growth. In terms of car use it is back where it was in 2001 at 0.31 work trips per person. It is the 2006 data point (whichever you use) that doesn’t fit the rest.

    • lefty

      Oh, and cycling had a negative coefficient (dropping) but it wasn’t significant.

  • Ak-Sam

    A multiline graph showing % change of each mode would be nice to see :)

  • Once again some great data.

    I suspect that the price of petrol from 2006 on wards was one of the main drivers of PT uptake.

  • Need to remember that multiple billions have been spent in order to speed and smooth the driver experience over this period. On the other hand almost no buslane or bike lane metres have been added and while serious money has been on electrification that of course is yet to manifest, in fact the only experience from this so far has been disruption to services.

  • Bryce P

    How do we change mode share? We could do a lot worse than copy this. http://bicycledutch.wordpress.com/2014/01/09/five-years-of-filming-anniversary-my-daily-commute/ (and it has a great video for those who don’t like reading)

  • -Phil_

    If you take the percentage changes over the 17 years it is a swing of 0.212% towards PT per year. That means that in 174 years PT will be a 50-50 share with private vehicles.
    83.8% of travel is by private vehicle – that is a massive figure and any back slapping about the death of the car is ridiculous. Lower fuel prices – which are a reality – will put even more people back into private vehicles.
    Yes PT is great but it will NEVER be as CONVIENIANT and NEVER be as COMFORTABLE as private transport.

    • Steve D

      > it will NEVER be as CONVIENIANT and NEVER be as COMFORTABLE as private transport.

      For some trips, sure. Which is why it’s all the more disappointing that, compared to PT, there’s been even less effort to make the other forms of private transport more attractive – walking and cycling.

      Although for some other trips, frequent, fast, grade-separated public transport can easily be more convenient than cars. Especially going to big events, or into major city centres. Or pretty much anywhere with limited capacity for parking.

  • -Phil_

    Steve – I stand corrected – you are right. For concerts and things like that it is more convenient to use PT. To be honest – I use PT a lot. I am a 2 min walk from the Northcote Point Ferry – why drive into town when you can have a nice ride on the harbour. In the UK I use PT to go into London because it is such a ball ache to park.
    My point is that for most people in Auckland commuting is always going to be more convenient and it is always more comfortable.

    • nonsense

      Yes it’s always more convenient because the whole society is paying for you to drive your car with the results seen in Stu.s post

    • Stu Donovan

      As per my comment on the other thread, transport investment priorities should focus on accommodating/facilitating growth (as per Government Policy Statement on Transport). If we analyse growth in journey to work, then we find that a disproportionate number of growth is occurring in public transport, walking, and cycling relative to their levels of investment.

      The fact that 83% of Aucklanders currently choose to drive to work is actually not very relevant to discussions of future investment: Their needs can be met by simply maintaining the current road network, which is quite cheap and certainly a reasonable thing top do.

      But road maintenance is a small piece of the transport funding pie. And one can acknowledge the value of maintaining existing roads while not supporting investment in new ones and/or bigger ones.

      Instead, I’d argue that investment in new/expanded infrastructure should focus on public transport, walking, and cycling. They are showing the most potential for growth.

    • Steve D

      > My point is that for most people in Auckland commuting is always going to be more convenient and it is always more comfortable.

      Today, that’s definitely true. But I do think in a lot of the city, that’ll become much less so over time.

      The Unitary Plan abolishes minimum parking requirements in the major regional centres like Newmarket, Manukau, Henderson and so forth, plus lots of generic business areas like Eden Terrace. Even in some “malls” like St Lukes and Sylvia Park. Given the tiny proportion of the city that’s actually going to be zoned for intensive residential, or any sort of business, that land is worth a fortune. It’s easy to see low-return surface parking being redeveloped.

      What’ll likely happen is that parking will be converted into higher-return retail, office and residential until the scarcity of parking finally drives parking prices high enough to make a decent commercial return. What are parking prices going to be like, if you’re competing with offices at $500/sqm? A permanent park in most strong regional centres is likely to be approaching CBD prices: hundreds of dollars a month.

      The other issue is traffic, which is pretty much at capacity. New Zealand doesn’t have the money or the will to knock down vast amounts of private property to widen significant numbers of roads, and pretty much every possible at-grade road project has already been built.

      Even if we don’t actually improve public transport (other than the inevitable CRL), it’ll still become more attractive by comparison with ever-worse congestion and ever-more-expensive parking. But increased patronage will bring more investment too, more frequent services, and that makes PT more attractive, in a virtuous cycle. There’s little scope for new private vehicle trips, so PT, walking and cycling are going to have to cater for the bulk of growth, even if they don’t meaningfully reduce existing traffic volumes.

      • -Phil_

        Steve,

        I am all for PT but you are right – it comes down to what we can afford and for me – right here right now – and for the foreseeable future – the cheapest way to provide PT is via roads.

        An Auckland with a proper rapid rail system is years and millions of people in growth away. I wonder if any of us alive today will see that.

        As for parking minimums. Hmmm – you want a city where people tarmac their front lawn just to park cars? Lets face it – there are precedents for that in the world :( Be careful of what you wish for – not every car space is going to be turned into a cafe.

        • Steve D

          > the cheapest way to provide PT is via roads.

          I do agree with you here, in a sense. I’d love to see major rail extensions or get the whole CFN built, but I think we’re pushing it financially to get that any time soon. The CRL will happen, but it’s probably going to be the biggest thing we do for fifteen years or more.

          Even that’s assuming we abandon new road building. We certainly don’t have the money for major roading projects, no matter what else we do, and I fear that we’re going to rack up huge amounts of debt trying.

          The one thing we do have in spades, though, is our existing under-prioritised road network. Green paint is very cheap, buses are cheapish. How about we put unbroken bus lanes on every route in the frequent network, and bump up frequencies whenever buses start filling up? We don’t need new roads or rail if we make better use of the ones we already have.

          The other big wins are cycling – which just needs fairly cheap reallocation and redesign of roadspace – and walking, which naturally grows when land use is allowed to develop in walking-friendly ways. Both are cheaper than trains.

  • -Phil_

    Stu – the PT/walking/cycling shows the most growth simply because no one is interested in doing it right now. a PT growth of 0.212% per year is actually depressingly small and while I am fully in agreement in growing that number it would be plain wrong for the Govt to ignore the 83% of Aucklanders who choose to use private transport to commute.
    We live in a democracy and while that may well be two wolves and a sheep voting for dinner – 86% of Aucklanders drive – that is a very clear message on where spending should be. What makes you think the 9% should dictate how the taxes are spent? Some sort of righteousness??

    • Steve D

      98.5% of New Zealanders use copper telephone lines (or radio waves) to get their Internet at the moment. Does that show that fibre to the home is a bad use of money? Or does it show that most people don’t have the option of fibre available yet?

      435,543 people drove to work on census day last year. 84,285 used another method. Neither of those numbers are going down, but neither have the slightest bit to do with how the next 50,000 people are going to get to work.

      I don’t think that 83% of Aucklanders “choose” to drive, anyway. They drive because that’s the only practical option available. Opinion polls show that half of them want more spent on public transport.

  • Ari

    Thanks for the stats. Looks good. I find it amusing that the heavily subsidized mode growth is losing to PT which has had miniscule investment. Imagine what would happen if we actually put real money into PT.

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