Which Australian city is sprawling the most?

Sat 3 December, 2016

For a while now, I’ve been tracking urban sprawl and consolidation in Melbourne, but some interesting recent research prompted me to compare Melbourne to the other large Australian cities.

My question for this post: How do Australian cities compare for growing out versus up? (by growth I’m talking about population)

Firstly, I need to define “outer” growth.

To do this, I’ve mapped the 2001, 2006, and 2011 ABS urban centre boundaries of each city. I’ve then looked at Statistical Area 3 regions within each Greater Capital City area that either saw substantial urban growth between 2001 and 2011, or were located on the fringe of the main urban area.

Here’s a map of Melbourne, with my designated “outer” areas shaded in a transparent blue:

The area in the middle is mostly shaded green – land considered by the ABS to be urban since at least 2001. There are a few yellow and orange areas (developed 2001-06 and 2006-11 respectively) that are not part the blue shaded “outer” area. The larger orange section visible in the south is mostly green wedge or industrial land, so does not represent growth of residential areas (maps for other cities below). The other yellow and orange areas are relatively small, and many have non-residential land uses.

I’ve done a similar process for Sydney, Perth, Adelaide, and the conurbation of South East Queensland (ie Brisbane, Gold Coast, and Sunshine Coast combined). See the end of this post for equivalent maps of these cities.

With an outer area defined for each city, I have calculated the annual population growth of these outer areas (based on 30 June estimates for each year), and compared it to growth of the city as a whole:

percentage-outer-city-population-growth

Perth comes out on top, with 81% of population growth in outer areas in 2015, with Sydney and Adelaide down at around 32%, while Melbourne and SEQ come in around 45-50%.

The SA3 population data goes back to 1991, which creates some interesting results in the early nineties (even though my defined “outer” areas are trying to measure growth from 2000 onwards). In Adelaide in 1993 the outer areas had “156%” of the city’s population growth – which actually means that the outer areas grew (by 4509 people) while the inner areas had population decline (by 1617 people). At the same time in Melbourne, “103%” of population growth occurred in the outer areas as there was a net reduction of 393 people in the inner areas of Melbourne. This reflects a previous trend for cities to grow mostly outwards until the mid 1990s, when urban densification took off. Indeed in another post, we saw the population-weighted density of Sydney, Melbourne, Adelaide and Brisbane bottom out in the mid 1990s:

SA3 cities pop weighted density time series 2

So is Perth the most sprawling large city in Australia? Well, yes in terms of percentage of population growth, but not in terms of absolute population growth in outer areas:

outer-city-population-growth

On my definitions of outer areas, Melbourne comes out top, with around 45,000 residents moving into growth areas in 2014-15. Perth almost matched Melbourne’s growth in 2012, but has fallen back since and in 2015 is closer to Sydney and SEQ. Adelaide just hasn’t seen a lot of population growth in recent decades.

Population growth in outer Sydney slowed dramatically between 2002 and 2006. The chart below shows there was also a slow down in non-outer areas, although it was a little less dramatic. Around this time Sydney also transitioned from around 50% of growth being in outer areas, down to around 30%.

Here is the annual population growth in the non-outer areas of each city:

nonouter-city-population-growth

Around 2007 there was an acceleration of population growth in non-outer areas in most cities (although there was a subsequent lull around 2010-2012).

A couple of things to note:

  • The outer areas will have some combination of urban growth and urban densification. My guess is that most population growth will be from urban sprawl, as urban consolidation is more likely to happen in the inner and middle suburbs. But my method doesn’t attempt to remove urban consolidation in outer areas.
  • You might be wondering about the inclusion of outer areas that are not experiencing urban growth. These areas are unlikely to have much population growth at all, so will have little impact on the calculations of percentage of growth in outer areas.

Finally, here are maps showing my defined “outer” areas of the other cities:

Sydney

sydney-cropped

I’ve used the full Greater Capital City area, which includes the Central Coast (Gosford / Wyong). This is arguably part of a conurbation with Newcastle but I’ve kept to the Greater Sydney boundary.  The large orange and yellow non-outer area to the west is mostly parkland or industrial, while the orange area to the south is mostly the Holsworth Military area which was defined as urban from 2011.

South East Queensland

seq-cropped

I’ve included all of Greater Brisbane, as well as the Gold Coast (as far as the border with NSW) and the Sunshine Coast. The conurbation population includes the established areas of the Gold Coast and Sunshine Coast as non-outer areas. The orange areas on the Sunshine Coast mostly contain National Parks and the airport, although it also includes the relatively new suburb of Peregian Springs, so not a perfect definition.

Perth

perth-cropped

The non-outer area is fairly well-defined as almost entirely urban in 2001. The entire of the City of Joondalup (on the northern coast, mostly surrounded by Wanneroo) counts as urban in 2001, although the suburb of Iluka in the north-western corner has developed more recently, so the calculation won’t be perfect.

Adelaide

adelaide-cropped

The two large orange areas in the non-outer area are non-residential, so there will be little fringe growth outside the blue area.


Are Melbourne’s suburbs full of quarter acre blocks?

Sun 22 May, 2016

A lot has been said about the great Australian dream of moving to the suburbs and living on a quarter acre block. But is Melbourne suburbia actually full of quarter acre blocks? Where are they to be found? Are they disappearing? This post delves into block sizes in Melbourne.

Where are the quarter acre blocks?

A quarter-acre translates to 1011.7 square metres in modern units, but for the purposes of this post I’ll allow some leeway and count any block between 900 and 1100 square metres. For this post I’ve also filtered out blocks in planning zones that cannot include dwellings (eg industrial areas), but that does mean I’ve included blocks in mixed use zones, commercial zones, etc. So not every block counted is residential. Also some larger blocks might contain multiple small dwellings but not actually be subdivided (eg a block of flats).

First up, here is a map of Melbourne showing the prevalence of quarter acre blocks. It looks like there are lots of them, but because the blocks are so small, the total area occupied by quarter-acre blocks is significantly over-represented on this large scale map.

Melbourne quarter acre block map

There are larger concentrations in the outer north-east and outer-east, but very few blocks in the current growth areas to the west, north and south-east.

Here are the top 20 suburbs for numbers of quarter-acre blocks:

Mooroolbark 1625
Rye 1545
Ferntree Gully 1504
Boronia 1471
Croydon 1437
Mount Martha 1430
Eltham 1229
Mount Eliza 1125
Werribee 1054
Sunbury 1035
Lilydale 996
Mornington 982
Reservoir 978
Balwyn North 936
Berwick 898
Upwey 897
Pakenham 772
Langwarrin 767
Kilsyth 732
Greensborough 724

There are almost 78,000 quarter-acre blocks within Melbourne’s Urban Growth Boundary, which sounds like a lot, but is only 3.75% of the 1.8 million blocks in my dataset.

So what are typical block sizes in Melbourne?

For this analysis I’m considering blocks within land use zones that can include dwellings, that are also within the urban growth boundary. But I’ve excluded blocks of less than 40 square metres on the assumption these are unlikely to contain dwellings.

Here’s the frequency distribution of block sizes in Melbourne:

The most common block size is 640-660 square metres, and 34.5% of blocks are between 520 and 740 square metres. The median is 540-560 square metres. 180-200 is the most common smaller block size, and there is a small spike in block sizes of 1000-1020 square metres, which includes the quarter-acre block. But quarter-acre blocks are certainly very uncommon.

I’ve calculated the median block sizes for all suburbs within Melbourne’s Urban Growth Boundary.

The inner city has median block sizes under 300 square metres, and 300-500 is typical in the inner northern and western suburbs. Block sizes are larger in the middle and outer eastern suburbs, older suburbs in the south-east, and blocks along the Mornington Peninsula. But the more recent growth areas to the west, north and south-east see median block sizes of between 400 and 500 square metres (purple), reflecting higher dwelling densities encouraged by current planning policy for growth areas. Quarter-acre blocks are the median only in places like Upwey, Belgrave and Portsea.

Inner city Carlton has the lowest median of 100-120 square metres, followed by Cremorne, North Melbourne, South Melbourne at 120-140 square metres, and then Abbotsford, Fitzroy North, Port Melbourne, Richmond, West Melbourne at 140-160 square metres. Urbanised suburbs at the other end of the scale include Park Orchards at 3020, Selby at 1440, and Warrandyte at 1260.

There are two interesting outliers in the central city: Southbank (in yellow) has a median block size of 980 square metres, and Docklands (in blue) has a median of 660 square metres. Both have been redeveloped in recent decades with many medium to high-rise apartment towers on those larger blocks.

Beyond these medians, there is a lot of variation within suburbs. Let’s go for a wander around the city.

Mooroolbark has the highest count of quarter-acre blocks and a median size of 840 square metres. As well as larger blocks, you can see a lot of further subdivision, particularly close to the train line (thin black line).

You may have noticed in the suburb map above a black coloured suburb in the middle south-eastern suburbs. That suburb is Clayton, and here is how it looks:

While blocks of 700-800 square metres were probably typical in the original subdivision, further subdivided blocks now outnumber the larger blocks, with a median of 260 square metres. Clayton of course is home to a major Monash University campus, and I suspect a lot of the smaller blocks house students.

A bit further down the line in Noble Park you can see extensive further subdivision near the rail line, surrounded by almost uniform blocks of 500-600 square metres:

Heading further south, Cranbourne is an interesting mix. The inner core (old town) has larger blocks but lots of further subdivision. This is surrounded by many blocks of around 700-800 square metres, but the most recent development has much smaller bocks, most less than 500. It’s a bit like tree rings, with each ring of incremental urban growth reflecting the preferred new block size of the time.

The area around Berwick also has a wide variety of block sizes, depending on the timing of development:

Here is the Frankston area:

Again significant further subdivision in central Frankston, a variety of block sizes in different parts of Langwarrin, and lots of large blocks in Frankston South and Mount Eliza (in some of the pink areas most blocks are over 2500 square metres).

In the middle northern suburbs you can see suburbs from an era when new block sizes were relatively large, and they’ve since had extensive subdivision. Here is Pascoe Vale:

Here is Reservoir. You can see smaller blocks in the surrounding suburbs:

The large block area to the west of the train line was apparently developed around the 1960s.

And to the west St Albans is another suburb with larger blocks being subdivided:

And further east there is a lot of further subdivision in Boronia and Bayswater, particularly near the rail stations:

The north-west corner of Templestowe has not too many larger blocks yet to be subdivided. But to the south-east you can see areas with blocks larger than 1200 square metres (light pink).

The area around Eltham has many large blocks, including many larger than quarter-acres. There has been quite a bit of subdivision around the rail stations however.

Another area with many large blocks is around Upwey/Belgrave:

A significant proportion of blocks are larger than a quarter-acre, with a median of 1060 in Belgrave, 1120 in Upwey, 1000 in Tecoma, and 980 in Upper Ferntree Gully.

If you want a quarter-acre block relatively close to the city, then Balwyn North has quite a few (many with swimming pools). Good luck saving a deposit for those.

But if a quarter-acre block isn’t big enough and you can afford the real estate, then you might want to try Canterbury or Deepdene, also relatively close to the city:

Or of course Toorak with plenty of very large blocks even closer to the city (although many will contain apartment buildings).

Essendon also has some larger blocks, including some quarter-acres:

There has been plenty of further subdivision, but there is also a stripe of green that is mostly in tact (a restrictive covenant applied perhaps?). You can also see the recent Valley Lake development in purple in Niddrie.

Most of the growth areas have small blocks, but here are some exceptions in eastern Doreen:

So there is plenty of variation in block sizes across Melbourne, but not that many quarter-acre blocks. Perhaps we should talk more about the one-seventh-acre block.

Data acknowledgement

This analysis was made possible with data available from data.vic.gov.au under a creative commons license. The data is Copyright © The State of Victoria, Department of Environment, Land, Water & Planning 2016.

I have used November 2015 property boundary data and May 2016 planning zones (sorry, not quite aligned, but this post has been a while in the making and the differences are unlikely to be significant).


How do Australian and European cities compare for population and area?

Sun 6 December, 2015

Following on from my previous post comparing the density of Australian and European cities, there has been some interest in the relative size of Australian and European cities. This post takes a quick look.

To make comparisons, I’ve taken the square kilometre population grid data for Europe and Australia, and summed the population and number of cells within the urban area/centre boundaries (as discussed in last post) that have at least 100 residents (ie 1 person per hectare or more) for each city. I’ve included this (arbitrary) threshold as some urban area boundaries seem to include some non-urban land. It means that I’m approximately measuring the populated areas of cities, and large parks, industrial areas, airports, etc may therefore be excluded in this analysis.

Here’s a chart of population versus populated area (click to enlarge):

 

So Melbourne is about the same size as London and Paris but has less than half the population. Brisbane is a similar size to Milan, with half the population. Perth is larger than Berlin, but has around half the population. Adelaide has a similar population to Seville and Sofia, which are about a third the size. Sydney has a similar population as Barcelona but is almost four times larger.

Because I couldn’t label all the cities in the chart above, here is a data table (smaller values in red, larger values in blue):

AU EU city data table
I’m hoping to add Canadian and US cities to my analysis soon.


Comparing the densities of Australian, European, Canadian, and New Zealand cities

Thu 26 November, 2015

[updated March 2016 to add Canadian and New Zealand cities]

Just how much denser are European cities compared to Australian cities? What about Canadian and New Zealand cities? And does Australian style suburbia exist in European cities?

This post calculates the population-weighted density of 53 Australian, European, and Canadian cities with a population over 1 million, plus the three largest New Zealand cities (only Auckland is over 1 million population). It also shows a breakdown of the densities at which these cities’ residents live, and includes a set of density maps with identical scale and density shading.

Why Population Weighted Density?

As discussed in previous posts, population-weighted density attempts to measure the density at which the average city resident lives. Rather than divide the total population of a city by the entire city area (which usually includes large amounts of sparsely populated land), population weighted density is a weighted average of population density of all the parcels that make up the city. As I’ve shown previously, the size of the parcels used makes a big difference in the calculation of population-weighted density, which makes comparing cities difficult internationally.

To overcome the issue of different parcel sizes, I’ve used kilometre grid population data that is now available for both Europe and Australia. I’ve also generated my own kilometre population grids for Canadian and New Zealand cities by proportionally summing populations of the smallest census parcels available.

Some measures of density exclude all non-residential land, but the square kilometre grid approach means that partially populated grid parcels are counted, and many of these parcels will include non-residential land, and possibly even large amounts of water. It’s not perfect, particularly for cities with small footprints. For example, here is a density map around Sydney harbour (where light green is lower density, dark green is medium density and red is higher density):

Sydney harbour

You can see that many of the grid cells that include significant amounts of water show a lower density, when it fact the population of those cells are contained within the non-water parts of the grid cell. The more watery cells, the lower the calculated density. This is could count against a city like Sydney with a large harbour.

Defining cities

The second challenge with these calculations is a definition of the city limits. For Australia I’ve used Urban Centre boundaries, which attempt to include contiguous urbanised areas (read the full definition). For Europe I’ve used 2011 Morphological Urban Areas, which have fairly similar rules for boundaries. For Canada I’ve used Population Centre, and for New Zealand I’ve used Urban Areas.

These methodologies tend to exclude satellite towns of cities (less so in New Zealand and Canada). While these boundaries are not determined in the exactly the same way, one good thing about population-weighted density is that parcels of land that have very little population don’t have much impact on the overall result (because their low population has little weighting).

For each city, I’ve included every grid cell where the centroid of that cell is within the defined boundaries of the city. Yes that’s slightly arbitrary and not ideal for cities with dense cores on coastlines, but at least I’ve been consistent. It also means some of the cells around the boundary are excluded from the calculation, which to some extent offsets the coastline issues. It also means the values for Australian cities are slightly different to a previous post.

All source data is dated 2011, except for France which is 2010, and New Zealand which is 2013.

Comparing population-weighted density of Australian, European, Canadian and New Zealand cities

AU EU CA NZ Population Weighted Density

You can see the five Australian cities are all at the bottom, most UK cities are in the bottom third, and the four large Spanish cities are within the top seven.

Sydney is not far below Glasgow and Helsinki. Adelaide, Perth and Brisbane are nothing like the European cities when it comes to (average) population-weighted density.

Three Canadian cities (Vancouver, Toronto and Montreal) are mid-range, while the other three are more comparable with Australia. Of the New Zealand cities, Auckland is surprisingly more dense than Melbourne. Wellington is more dense that Vancouver (both topographically constrained cities).

But these figures are only averages, which makes we wonder…

How much diversity is there in urban density?

The following chart shows the proportion of each city’s population that lives at various urban density ranges:

AU EU CA NZ urban density distribution

Because of the massive variations in density, I had to break the scale interval sizes at 100 persons per hectare, and even then, the low density Australian cities are almost entirely composed of the bottom two intervals. You can see a lot of density diversity across European cities, and very little in Australian cities, except perhaps for Sydney.

You can also see that only 10% of Barcelona has an urban density similar to Perth or Adelaide. Which makes me wonder…

Do many people in European cities live at typical Australian suburban densities?

Do many Europeans living in cities live in detached dwellings with backyards, as is so common in Australian cities?

To try to answer this question, I’ve calculated the percentage of the population of each city that lives at between 10 and 30 people per hectare, which is a generous interpretation of typical Australian “suburbia”.

AU EU CA NZ cities percent at 10 to 30 per hectare

It’s a minority of the population in all European cities (and even for Sydney). But it does exist. Here are examples of Australian-style suburbia in outer Hamburg, Berlin, LondonMilan, and even Barcelona (though I hate to think what some of the property prices might be!)

How different is population-weighted density from regular density?

Now that I’ve got a large sample of cities, I can compare regular density with population weighted densities (PWD):

PWD v regular density 2

The correlation is relatively high, but there are plenty of outliers, and rankings are very different. Rome has a regular density of 18, but a PWD of 89, while London has a regular density of 41 and PWD of 80. Dublin’s regular density of 31 is relatively close to its PWD of 47.

Wellington’s regular density is 17, but it’s PWD is 49 (though the New Zealand cities regular density values are impacted by larger inclusions of non-urbanised land within definitions of Urban Areas).

So what does the density of these cities look like on a map?

The following maps are all at the same scale both geographically and for density shading. The blue outlines are urban area boundaries, and the black lines represent rail lines (passenger or otherwise, and including some tramways). The density values are in persons per square kilometre (1000 persons per square kilometre = 10 persons per hectare). (Apologies for not having coastlines and for some of the blue labels being difficult to read).

Here’s Barcelona (and several neighbouring towns), Europe’s densest large city, hemmed in by hills and a coastline:

Barcelona

At the other extreme, here is Perth, a sea of low density and the only city that doesn’t fit on one tile at the same scale as the other cities (Mandurah is cut off in the south):

 

Perth

Here is Paris, where you can see the small high density inner core matches the high density Metro railway area:

Paris

Similarly the dense inner core of London correlates with the inner area covered by a mesh of radial and orbital railways, with relatively lower density outer London more dominated by radial railways:

London

There are many more interesting patterns in other cities.

What does this mean for transport?

Few people would disagree that higher population densities increase the viability of high frequency public transport services, and enable higher non-car mode shares – all other things being equal. But many (notably including the late Paul Mees) would argue that “density is not destiny” – and that careful design of public and active transport systems is critical to transport outcomes.

Zurich is a city often lauded for the high quality of it’s public transport system, and it’s population weighted density is 51 persons/ha (calculated on the kilometre grid data for a population of 768,000 people) – which is quite low relative to larger European cities.

In a future post I’ll look at the relationship between population-weighted density and transport mode shares in European cities.

All the density maps

Finally, here is a gallery of grid density maps of all the cities for your perusing pleasure (plus Zurich, plus many smaller neighbouring cities that fit onto the maps). All maps have the same scale and density shading colours.

Please note that the New Zealand and Canada maps do not include all nearby urbanised areas. Apologies that the formats are not all identical.


Updates to transport trends – June 2015

Wed 10 June, 2015

I’ve recently updated three posts on this blog to include the latest available data. Here is a short summary.

Transport greenhouse gas emissions

Australian domestic transport emissions have continued to rise and is now the sector with the biggest percentage growth since 1990. Domestic aviation emissions have tripled since 1990. Car emissions per kilometre were improving until 2007, but we appear to have gone backwards since then.

Australia transport emissions growth by sector 2

 

Full post here.

Melbourne urban sprawl and consolidation

Outer growth areas of Melbourne now account for around 43% of population growth, but urban consolidation in the inner suburbs continues to exceed projections.

actual and VIF2014 by region 2

 

Full post here.

Are Australian cities becoming denser?

This fully revised post looks at calculating population-weighted density using a new population grid for Australia, which finally allows for an internationally comparable measure of city density. I’ve also taken a look at some smaller Australian cities. The data suggests Sydney, Melbourne and Perth have been densifying fastest in more recent years.

SA2 pop weighted density large cities time series

Full post here.

 

 


Trends in driver’s licence ownership in Australia

Mon 9 March, 2015

Recent research has talked about “millennials” being less likely to get their driver’s licence at younger ages, with data showing a decline over the 2000s. But is this trend continuing? This post checks out the latest data to see if the decline is still happening.

While I’m at it, I’ll look at licence ownership by age and gender (are young men more likely to have a licence than women?) and trends for older persons (are people holding onto licences longer into old age?). There’s also a strange quirk for people born in 1945/6.

This post analyses available state-based data on driver’s licence ownership in Australia in recent years. In this post some of the data sets I’ve used include learner’s permits, and some only count “independent” licences (watch for notes).

How does licence ownership vary with age?

I have access to licensing data for four Australian states that allows a quite detailed analysis (three publicly, and VicRoads kindly let me access theirs).

The following chart shows licence ownership for Victoria, South Australia and New South Wales by individual age for the most recent year available at the time of writing (combining licensing data with ABS state population estimates by single year of age to calculate ownership rates):

license ownership aus by age

Licence ownership peaks between ages in the mid-thirties to late sixties, then falls away with age thereafter. There is certainly a pattern of people in their 20s and early 30s being less likely to have their licence.

The main difference for the younger ages is that the Victoria data include independent licences only (ie excludes people with a learner’s permit). Also, from what I understand, the minimum age for an independent driver’s licence is 17 in most states, except in Victoria where it is 18, and the Northern Territory where it appears to be theoretically possible at age 16 and 6 months. The minimum age for a learner’s permit is 16 years, except in the ACT where it is 15 years and 9 months.

The Victoria data is generally higher than the other states from around age 32, with some results calculated as high as 99.8%. The Victoria data includes suspended licences, which may not be the case for other states, and there may be other minor differences in the way the data is counted. But it is interesting that Victorian ownership rates are up to 10% higher for older age groups. I’ll look at those trends and patterns in more detail shortly.

I’ve previously looked at driver’s licence ownership using VISTA data (Victorian household travel survey 2007-2009) which shows a similar pattern but with less detail:

car license by age

How does licence ownership vary with gender (and age)?

First up, New South Wales:

nsw license ownership by age and gender

Age 30 is the age under which females are more likely to have a licence (or learner’s permit), and after which males are have higher rates of licensing. The difference in licensing between the genders grows very large for older ages. This might be explained by women of older generations being less likely to have ever obtained their licence, and/or men stubbornly holding onto their licence for longer than they should.

Here’s the same data for South Australia:

sa license ownership by age and gender

The gender flip occurs around age 27 – with younger women more likely to have their driver’s licence.

Queensland data is available with slightly less age resolution:

qld license ownership by age and gender

The gender flip point occurs sometime between ages 21 and 24.

I really wasn’t expecting younger females to be more likely to have a licence than males. Is this just something to do with learner’s permits?

I can only answer that question with Queensland data:

qld learner and independent age gender

This shows women in Queensland are more likely to have their learner’s permit than men (at any age). However, men are actually more likely than women to have an independent licence from age 20 onwards, as women appear to spend more time with their learner’s permit. It would be interesting to look at this for other states, but alas the data isn’t readily available.

You may also have noticed the South Australia and Queensland data suggests around 101% of men in some age groups have their driver’s licence. This suggests imperfect data – perhaps double counting people with endorsements for higher classes of vehicle or people who have both car and motorbike licences, or imperfect ABS estimates of people at each individual age. So licensing data needs to be read with caution, with a focus on the trends and patterns rather than exact numbers.

Licence ownership trends of younger people

Here is independent licence ownership rates in Victoria for younger people:

license ownership Victoria younger age and year

There are clear and sizeable downward trends in licence ownership rates amongst most ages, with most dropping by around 12% over 13 the years. There was a slight rise in most age groups in 2009 but then a quite significant fall between 2009 and 2010, particularly 18 and 19 year olds. The graduated licensing system was introduced between January 2007 and July 2008, and I’m yet to find references to changes in rules around 2009 or 2010. so I’m not sure how to explain the changes in 2010. That said, when I look at the data for 2010, there are a few anomalies in patterns in other age groups, so there may be some small data errors.

The rate of licence ownership of 18 year olds was however relatively steady between 2001 and 2008, but then dropped significantly from 2010. The minimum time period to hold a learner’s permit became 12 months in July 2007, making it harder to obtain your probationary licence by age 18. There is a peak of licence ownership at age 18 in (June) 2009 – these people will have turned 16 in the financial year 2006-07 and so probably escaped the new licensing regime (I suspect this cohort made more effort to get their learner’s permit before 1 July 2007).

I also note that the declines appear to have largely levelled off for most ages since around 2011. I don’t have much data about learner’s permit holders in Victoria, but some data published shows that the average time spent on L plates in Victoria for people aged 17-20 increased from around 60-70 weeks in 2000 to around 100 weeks in 2010, following the graduated licensing scheme introduction.

Have we now stabilised at new lower levels? More on that shortly.

Readers of this blog will note that several transport trends changed direction in 2011. That was about the time that public transport patronage growth in Melbourne slowed down, and mode share stabilised. Here’s the Melbourne mass transit mode share and young persons licensing rates charted together:

vic young licensing and PT mode share

(mass transit mode share from other BITRE yearbook data)

Or if you look at this as a correlation:

vic young licensing and PT mode share correlation

That’s a strong correlation. Given that younger people dominate public transport patronage, this isn’t hugely surprising. The major deviation from the trend is 2009, which is perhaps explainable through changes to the licensing regime, although between 2001 and 2005 there was a reduction in licence ownership without mode shift to mass transit.

So why has the trend towards lower licence ownership of younger people stopped in Victoria? Other researchers might have to answer that question.

Here is data for young people in New South Wales (note: data includes learner’s permits):

license ownership NSW younger age and year

Very different trends! Most age groups trended down between 2007 and 2010 but then many bounced up again thereafter.

So is this completely different trend because it includes learner’s permits? Unfortunately I don’t have single-age based data for people with independent licences, but I do have it for age groups:

independent license ownership NSW younger age group and year

The trends are similar. Independent licence ownership rates have dropped by around 3-5% in the younger age brackets over the nine years. There was a larger dip around 2009, followed by small rises in some age brackets since. Otherwise things look pretty stable, and very different to Victoria (and note that Sydney has had much less public transport patronage growth than Melbourne over the same time).

If I put learner’s and independent licences together and look at 20-24 year olds, there is a slightly higher proportion with their learner’s permit in more recent years (8% to 11%). So this suggests people are probably staying on their Ls for slightly longer.

NSW learner v independent young people

Do the trends in NSW licence ownership correlate with Sydney mass transit mode share?

NSW young licensing and PT mode share correlation

Not nearly as much as for Victoria and Melbourne.

What is interesting in the NSW data is that there appears to be a pattern that varies by birth year. I’ve adjusted the layout of the data tables such that each row represents people in a single birth year (well, birth financial year, if you will). This data includes learner’s permits.

nsw license ownership by birth year and age

Licence ownership rates were relatively higher for people born 1992 onwards (although curiously they appeared to have declined after age 21, which perhaps might be a result of immigration – not sure). In NSW, the birth years of approximately 1982 to 1991 appear to have had relatively lower rates of licence ownership.

Only six years of data is available for South Australia, but there is a pattern of higher licence ownership for people born from around 1993 onwards (data includes learner’s permits), but it might be trending downwards again from birth years 1996 onwards:

sa license ownership by birth year and age

(note: the only available South Australia data for 2010 is for January – I have interpolated to estimate June 2010 numbers. The most recent data is for March 2014 – I have interpolated the population estimate accordingly but in the figure above the bottom numbers in each column are for people born in the 12 months to March 1998, not 12 months to June 1998).

Queensland data only reports single year licence ownership to age 20, but a much longer time series is available:

qld license ownership by birth year and age

Again, there is a range of birth years from around 1984 to 1990 with relatively lower licence ownership. In July 2007 the minimum age for a learner’s permit dropped to 16, which would explain the massive increase in learner’s permit ownership for 16 year olds. This seems to correspond to increased licensing rates for birth years 1993 onwards.

Although Victoria hasn’t had a bounce in licence ownership rates for young people, the birth year trends do show the downward trend finishing with births around 1990. In fact, from that birth year the rate of licence ownership at age 21 went up slightly, which might reflect that it is easier to obtain a probationary licence from that age (as a learner logbook is no longer required). The decline in licensing rates seemed to begin around birth year 1980.

vic license ownership by birth year and age

The following table summaries the birth years of lower licence ownership in each state, and compares these birth years with the first birth year impacted by graduated by graduated licensing (assuming people obtain their learner’s permit at age 16):

Lower licence
ownership birth years
Graduated licensing started
Start End Start First birth year
New South Wales 1982 1991 2000 1984
Victoria 1980 1990 2007 1991
South Australia ? 1993 2005 1989
Queensland 1985 1990 2007 1991

There appears to be a fairly consistent cohort of people born between around 1980-5 and 1990-3 who have been less likely to get their licence at a younger age. In Victoria and Queensland they weren’t faced with the new graduated licensing system if they got their learner’s permit at age 16. In fact, licensing rates stopping declining in the birth years first fully subjected to graduated licensing in Queensland and Victoria – the opposite of what you might expect!

Dr Alexa Delbosc at Monash University has led much interesting research into reasons for the downwards trend of licence ownership in Australia (amongst others). Perhaps this new evidence of a reversal/stabilisation of the trend might explain some things further, or need a new explanation in itself.

What about licence ownership of older people?

First up, Victoria:

vic older license ownership rates

Licence ownership rates increased in Victoria until 2011 in most age groups, probably reflecting people living healthier for longer.  However licence ownership rates fell from 2011 onwards for those over 80 (despite Victoria not having mandatory testing for older drivers). It might be explained by a change to a 3 year licence renewal period for those over 75, but I cannot confirm when that change was implemented. I’m also at a loss to explain the blips in the 2009 data for those 90+.

Here’s the same for New South Wales, where car drivers need to have an annual medical review from age 75, and have to pass a practical test to keep an unrestricted licence from age 85. For those 75+, licensing rates are considerably lower than in Victoria.

nsw older license ownership rates

While the Queensland data provides less resolution of age groups, it shows the trend of increasing licence ownership over a longer period of time, although with a levelling out for those 60-74 from around 2013.

qld older license ownership rates

And for completeness, here is five year’s worth of data available for South Australia, not showing any dramatic trends:

sa older license ownership rates

Finally, you might have spotted a blip in the first chart of this post around age 68 (you were looking at it carefully, right?). Zooming in and changing the X axis to birth year we see an interesting anomaly:

license ownership rates people born in 1960s

Years on the X axis are actually financial years (ending June). People born in 1946/7 are 10% more likely to have their driver’s licence than people born in 1945/6, and this is consistent across three states!

This year of relatively lower licence ownership is for people born immediately after World War II, and who around 19 years of age when Australia sent troops to the Vietnam War (although many men in the next birth year would also have gone to Vietnam). I wondered if it might be related to the Vietnam War, but then the trend applies more so to women than men, as shown in this NSW data:

NSW 1940s brith years by gender

I then thought it might be to do with being born whilst Australia was recovering from the war and healthy food and good medical care might have been less available, resulting in a mini-generation of people less likely to be able to get their driver’s licences later in life.

The census provides one indicator of disability in terms of people recorder as “need assistance with core activities”. While people born between 1945 and 1949 seem to be slightly more likely to have a disability (compared to the general pattern across ages, supporting the post-war lower health hypothesis), the 1946 age year doesn’t stand out as much different to neighbouring years.

aus disability by birth year

Another explanation might be that ABS have inaccurately estimated the population born in that year.

Can anyone else shed more light on this anomaly?


What does the census tell us about cycling to work?

Mon 27 January, 2014

Who is cycling to work? Where do they live? Where do they work? How old are they? What work do they do? Do men commute by bicycle more than women? How far are cyclists commuting? What other modes are cyclists using?

The census provides some answer to these questions for the entire Australian working population, albeit for one winter’s day every five years.

This post builds on material I presented at the Bike Futures 2013 conference, using census data from across Australian with a little more detail on capital cities and my home city Melbourne.

It’s not a short post, so settle in for 13 charts and 17 maps of data analysis.

How has cycling mode share changed over time?

The first chart shows the proportion of journeys to work by bicycle (only) in Australia’s capital cities.

Cyclcing only mode share for cities time series

Darwin appears to the capital of cycling to work, although it is quickly losing ground to Canberra (unfortunately I don’t have figures for Darwin pre-1996).  The census is conducted in Darwin’s dry season, but other data suggests there is little difference in bicycle activity between the wet and dry seasons.

Melbourne has shown very strong growth since 2001 and Sydney showed strong growth between 2006 and 2011. Cycling mode share has grown in all cities since 1996.

Mode shares collapsed in Adelaide, Sydney, Brisbane, and Melbourne between 1991 and 1996, which many people have attributed to the introduction of mandatory helmet laws (Alan Davies has a good discussion about this issue on his blog).

But as I pointed out at the start, census data is only good for one winter’s day every five years. Does the weather on these days impact the results?

Here is a chart roughly summarising the weather in (most of) the capital cities for 2001, 2006 and 2011 in terms of minimum temperature, maximum temperature and rainfall. It doesn’t cover wind, nor what time of day it rained (although perhaps some fair-weather cyclists might avoid riding on any forecast rain). It also fails to show the sub-zero minimums in Canberra (involves asking too much from Excel).

Census day weather

You can see that 2011 was wetter in Adelaide and Hobart than previous years, and this coincides with lower cycling mode shares in these cities in 2011. So census data is quite problematic from a weather point of view. That said, most cities had very little or no rain on the last three census days.

Where were the commuter cyclists living and working?

Other posts on this blog have also covered some of these maps, but not for all cities.

Some of the following maps are animated to show both 2006 and 2011 results, and note that the colour scales are not the same for all maps. I’ve sometimes zoomed into inner city areas when these are the only places with significant cycling mode share. White sections on maps represent areas with low density, or where the number of overall commuters was very small (sorry I haven’t gone to the effort of making every map 100% consistent, but rest assured the areas in white are less interesting). Click on the maps to see more detail.

Canberra

Firstly home locations:

ACT 2011 bicycle

The cycling commuters mostly appear to be coming from the inner northern suburbs. I don’t know Canberra intimately, but Google maps doesn’t show a higher concentration of cycling infrastructure in this area compared to the rest of Canberra.

Secondly, bicycle mode share by work destination (at the larger SA2 geography):

Canberra 2011 SA2 dest bicycle any

The highest mode share was 12% in the SA2 of Acton, which is dominated by the Australian National University. Perhaps a lot of the university staff live in the inner northern suburbs of Canberra?

Melbourne

By home location:

Melb bicycle any zoom

Cycling mode share is highest for origins in the inner northern suburbs and has grown strongly since 2006. There’s also been some growth in the Maribyrnong  and Port Phillip council areas off a lower base.

By work location (note: this data is at the smaller destination zone geography):

bicycle mode share DZ Melbourne inner

Cycling to work boomed in inner Melbourne between 2006 and 2011, particularly to workplaces in the inner north. Princess Hill had the highest bike share of 14% in 2011 (possibly dominated by Princess Hill Secondary College employees), followed by a pocket of south-west Carlton that jumped from around 5% to 13%. Apart from the inner north, there were notable increases in Richmond, Balaclava, Yarraville and Southbank. Cycling rates within the CBD are relatively low, perhaps reflecting limited cycling infrastructure on CBD most streets in 2006 and 2011.

Adelaide

Firstly, by home:

Adl bicycle any zoom

Adelaide appears to lack any major concentrations of cycling, although slightly higher levels are found just outside the parkland surrounding the CBD.

Secondly, bicycle mode share by work destination at the (larger) SA2 geography:

Adl 2011 SA2 dest bicycle

The numbers are all small, with 3% in the (large) Adelaide CBD. I imagine a map based on destination zones might show some pockets with higher mode share, but that data isn’t freely available unfortunately.

Perth

By home location:

Perth cycling inner

The inner northern and western suburbs, and south of Fremantle seem to be the main areas of cycling growth.

For workplaces at the larger SA2 geography:

Perth 2011 dest SA2 bicycle

The highest mode share was in ‘Swanbourne – Mount Claremont’, only slightly ahead of ‘Nedlands – Dalkeith – Crawley’ – which contains the University of Western Australia. The Fremantle SA2 (with 3% bicycle mode share by destination) includes of Rottnest Island where around 20% of the 73 resident commuters cycled to work, but the result will be easily dominated by the mainland Fremantle section.

Again, I suspect some smaller pockets would have had higher mode shares if I had access to destination zone data.

Brisbane

By home location:

Bris cycling

There was significant growth in cycling from the West End, and around the University of Queensland/St Lucia – which may be related to the opening of the Eleanor Schonell Bridge (after the 2006 census) which only carries pedestrians, cyclists and buses.

By work location (at larger SA2 geography):

Bris 2011 dest bicycle

The highest share was in St Lucia – which is probably dominated by the University of Queensland. Neighbouring Fairfield – Dutton Park came in second. These two areas are directly joined by the Eleanor Schonell Bridge which provides cycling a major advantage over private transport. It seems to have been quite successful at promoting cycling in these areas.

Sydney

First by home location:

Sydney cycling zoom

There were quite noticeable shifts to cycling in the inner south and around Manly.

By work location (by smaller destination zone geography):

Syd dest bicycle

There was strong growth, again in the inner southern suburbs. In 2011 bicycle mode share was highest in Everleigh (11.5%) following by the University of NSW (Paddington) at 7.9% (excluding travel zones with less than 200 employees who travelled).

Rural Australia

Here’s a map showing bicycle share by SA2 workplace location for all of Australia, which gives a sense of bicycle mode shares in rural areas.

Australia 2011 dest bicycle mode share

Higher regional/rural bicycle mode shares are evident in southern Northern Territory (Petermann – Simpson), Katherine (NT), the Exmouth region, the Otway SA2 on the Great Ocean Road in western Victoria, and Longford – Loch Sport in eastern Victoria. I’ll let other people explain those.

The SA2s in Australia with the highest cycling mode shares in 2011 (by home location) were:

  • Lord Howe Island, NSW: 21%
  • Acton, ACT (covering Australian National University): 12%
  • Port Douglas, Queensland: 10%
  • Parkville, Victoria (covering the University of Melbourne main campus): 8%
  • East Side, Northern Territory (Alice Springs): 8%
  • St Lucia, Queensland (covering the University of Queensland): 8%

How far did people cycle to work? (in Melbourne)

It is difficult to get precise distances for journeys to work, but approximations are possible. I’ve calculated the approximate distance for each journey to work by measuring the straight line distance between the centroid of the home and work SA2s and then rounded to the nearest whole km. To give a feel for how this looks, here is a map showing inner Melbourne SA2s and the approximate distances between selected SA2s:

SA2 distances sample map

This distance measure generally works well in inner city areas. However in the outer suburbs SA2s are often much larger in size, and sometimes only partially urbanised. However as we’ve seen above the volumes of cycling journeys to work are very low in these places, so that hopefully won’t skew the results signficantly.

2011 Melb JTW cycling distances

Two-thirds of cycling journeys to work in Melbourne were approximately 5km or less, with 80% less than 7 km, and 30% were 2 km or less.

The longest commute recorded within Greater Melbourne was approximately 44km.

Was cycling combined with other modes?

The following chart shows that bicycles were seldom combined with other modes:

cycling - presence of other modes 2006 2011

Around 16-17% of cycling commuters in the four largest cities in 2011 involved another mode. Use of other modes with cycling grew in all cities between 2006 and 2011

The next chart shows what these other modes were:

Other modes with cycling 2011

Sydney, Melbourne, Brisbane and Perth had high rates of bicycle use with trains, while combining car and bicycle was more common in the smaller cities.

The next chart shows the number of trips involving bicycle and trains in 2006 and 2011:

JTW bicycle + train raw numbers

The chart shows the relative success of Melbourne Parkiteer program of introducing high quality bicycle cages at train stations, which has helped boost the number of people access the train network by bicycle by around 600 between 2006 and 2011. I understand a similar project has been undertaken in Perth which saw growth of around 250.

In Melbourne, the home locations for people using bicycle and train are extremely scattered – the following map shows a seemingly random smattering:

Melb bicycle + train

How does commuter cycling vary by age and sex?

bicycle mode share by age sex

This chart shows remarkably clear patterns. Males were much more likely to cycle to work. Teenage boys (particularly those under driving age) had the highest cycling mode shares (with teenage girls much less likely to cycle). The next peak for men was around the mid thirties, and women’s mode share peaked around ages 28-32.

Where are women more likely to cycle to work?

Women are sometimes talked about as the “indicator species” for cycling – ie if you have large numbers of women cycling compared to men then maybe you have good cycling infrastructure that attracts a broader range of people.

The census data can shed some light on this. For each SA2 in Melbourne, I have calculated the male and female cycling mode shares both as a home origin, and as a work destination (this analysis looks at people who only used bicycle (and walking) in their journey to work). I’ve then calculated the ratio of male mode share to female mode for each area (SA2).

I’ve used the ratio of mode shares in preference to the straight gender split of cycling commuters – as female workforce participation is generally lower and there can be spatial variations in the gender split of the workforce. 46% of all journeys within Greater Melbourne in the 2011 census were by females, but only 28% of cycling journeys to work were by females.

The following map shows the ratio of male to female cycling mode shares by home location for SA2s (with more than 50 commuter cyclists, and where the bicycle mode share is above 1%):

Melb 2011 cycling gender ratio home

Areas attracting comparable female and male bicycle shares include the inner northern suburbs and – curiously – Toorak (probably many using the off-road Gardiners Creek and Yarra Trails to access the city centre).

Here’s a similar map, but by workplace areas:

Melb 2011 cycling share gender ratio WP

The patterns are much more pronounced. Six SA2s had higher female mode shares than male: Yarraville, Fitzroy North, Brunswick East, Ascot Vale, Carlton North – Princes Hill, and Elsternwick.

The areas with near-1 ratios of male to female mode shares were similar to the areas with higher total cycling mode shares. The following chart confirms this relationship (note areas with cycling mode shares below 1% not shown):

gender ratio and overal mode share

What this also shows is that home-area mode shares reach much higher values than workplace-area mode shares. Perhaps the secret is in the home-area cycling infrastructure? Or perhaps it’s more to do with the residential demographics?

See the Bicycle Network Victoria website for more data about female cycling rates in Melbourne.

Do women cycle the same distances as men?

Again using the approximate straight line commuting distances (as explained above) the following chart shows that women’s cycling commutes are a little shorter than men’s, but not by much:

commute distance and gender

The median female cycling commute was approximately 1.8 km shorter than for males.

What types of workers are more likely to cycle to work?

Firstly, I’ve looked at the differences between public and private sector employees.

Before I dive into the data, it’s important to recognise that different types of workers are not evenly spread across Australia. Some types of jobs concentrate in city centres while others might be more likely to be found in the suburbs or the country. Therefore many of the following charts show results for Australia as a whole, but also for people working in central Melbourne (the SA2s of Melbourne, Carlton, Docklands, East Melbourne, North Melbourne and Southbank), which has a relatively high rate of cycling to work.

The data suggests public servants were much more likely to cycle to work:

cycling by employer type

The local government result has prompted me to calculate the cycling mode shares for local government workers across Australia (assuming workers work within the council for which they work). Here are bicycle mode shares for the top 20 councils for employee cycling mode share in the census:

Council State Bicycle mode share
Tumby Bay (DC) SA 23.5%
Kent (S) WA 18.8%
Carnamah (S) WA 16.0%
Central Highlands (M) Qld 14.3%
Uralla (A) NSW 13.8%
Wakefield (DC) SA 13.5%
Nannup (S) WA 12.5%
Broome (S) WA 12.1%
Alice Springs (T) NT 11.8%
Narembeen (S) WA 11.5%
Blackall Tambo (R) Qld 11.3%
Kowanyama (S) Qld 11.2%
Exmouth (S) WA 11.1%
Yarra (C) Vic 10.4%
Glamorgan/Spring Bay (M) Tas 8.7%
Torres (S) Tas 8.6%
Yarriambiack (S) Qld 8.3%
Mallala (DC) Vic 8.0%
Richmond Valley (A) NSW 7.2%
McKinlay (S) Qld 6.7%

Most of the top 20 are non-metropolitan councils. Melbourne’s City of Yarra is the top metropolitan city council (within Greater Melbourne the next highest councils are Moreland 6.1%, Port Phillip 5.6%, Melbourne 5.6% and then Stonnington 4.9%).

National government employees had the highest bicycle mode share of all of Australia. I suspect this relates to university staff, as many of the earlier maps showed university campuses often had relatively high rates of employees cycling (85% of “higher education” employees count as “national government” employees).

The census data can also be disaggregated by income:

cycling mode share by income

Cycling mode shares were highest for people on high incomes. Initially I thought this might reflect the fact that high income jobs are often in city centres were cycling is relatively competitive with private and public transport. However, even within central Melbourne workers, cycling rates are higher for those on high incomes (curiously with a second peak for those on incomes between $300 and $399 per week).

Does cycling to work make you healthier and therefore more likely to get promoted and earn a higher income? Or are employers offering workplace cycling facilities to attract highly paid staff? I haven’t got data that answer those questions.

Consistent with higher rates of cycling for higher income earners, those in more highly skilled occupations were more likely to cycle to work:

cycling mode share by profession

I suspect this might reflect the presence/absence of workplace cycling facilities (perhaps office workplaces are more likely to provide cycling facilities than retailers for example) and/or the ability to afford to live close to work (which makes cycling easier).

Are recent immigrants more likely to ride to work?

This one really surprised me and I only investigated it because it was possible to do. The census asks what year people migrated to Australia (if not born here), and it turns out that recent immigrants were much more likely to cycle to work:

cycling mode share by migration year

This might be explained by the demographics of recent immigrants (eg car ownership, home location, income levels, occupation and age).

I’d welcome comments on any other trends people might spot in the data.