The demography of employment part one: a suburban economy

This isn’t to say that the CBDs and their fringe commercial areas aren’t numerically large in terms of employment (they are). It simply means that their geographic dominance of our metropolitan wide employment distribution isn’t what many may have otherwise presumed. In other words, their share of the city wide jobs cake is a minority one. 

If this is surprising, what will also come as a surprise is that in the past decade, suburban jobs have been growing as fast or faster than in the inner city, meaning that CBDs are only holding their share, or losing their share, to suburban employment. This has come about despite what has arguably been a decade or two of intensive debate and policy investment into our inner city locations.

For example, in 2001 the Brisbane CBD’s share of metro wide employment was 14.3%. Over the ten year period from 2001 to 2011, this share actually fell to 12.5%. Including the city fringe areas saw the ratio slip marginally from 19% to 18.8% over the same period, suggesting a leakage of sorts from the CBD to city fringe areas. CBD employment actually grew in that period by 18,793 jobs but what the data reveals is that suburban employment in the Brisbane metro grew faster and by much more – an increase of nearly a quarter of a million jobs across the Brisbane metro region compared with the 18,793 increase for the CBD. 

In Sydney, the CBD and inner city areas accounted for 15.1% of jobs in greater Sydney in 2001. By 2011, this proportion had changed little to 15.6%. (Boundary changes by the ABS over the period make CBD-only comparisons difficult). An increase of more than 40,000 jobs in the city area over that time was dwarfed by the increase of more than 200,000 jobs across greater Sydney in the same period. Hence the ratio remained unchanged.

In Melbourne, the CBD share of metro wide employment was only 10.2% in 2001. Ten years later, it too had changed little, reaching only 10.6% (although a slightly larger boundary in 2011 would account for this increase). The inclusion of the Docklands and Southbank precincts over this period sees the ratios move from 12.1% of greater metro Melbourne jobs in 2001 to 14.3% by 2011 – a significant increase of sorts, which points to the impact of these new precincts on spatial employment patterns in Melbourne. But still, the combined areas of the Melbourne CBD, Docklands and Southbank account only for one in every seven jobs across the metropolitan region. Hardly a dominant position. 

Finally the trend is not explained by the much promised transition to ‘telecommuting’ or ‘work from home’ occupations. Like many predicted widespread social changes, the reality doesn’t live up to the promise. ‘Work from home’ employment accounts for less than 5% of all jobs and this proportion has actually decreased since 1991. 

Implications

For starters, if you think your bus or train to the CBD is more crowded, you’d be right. There are more jobs in the city centres now than 10 years ago - significantly more. But you’d likewise be correct if you were a suburban worker, grumbling that your suburban roads were now more congested. There are many times more jobs spread across suburban locations than there are in the city centre, and these jobs have increased numerically by much larger numbers (albeit spread over larger areas). And of course, if your commute to your suburban workplace takes you through an inner city road or transit node, you have a double whammy effect.

There are a number of quite significant public policy implications that suggest themselves based on this evidence. Public transport policy is just one. Our public transport systems are mostly based on a hub and spoke system (particularly for fixed routes as with rail) where the hub is the CBD and the spokes spread out. This system serves a highly centralised employment model but is notoriously inefficient (and prohibitively costly) when it comes to decentralised employment. 

If typically our CBDs contain only 10% to 13% of broader metropolitan area jobs, even with unlimited budgets, the capacity to reach ever higher proportions of overall public transit use are virtually non-existent simply because the networks will struggle to take people where their jobs are (overwhelmingly in the suburbs). This reality of employment distribution is something which receives very little prominence in public policy discussions about public transport investment; perhaps it should receive more? If only 10% to 14% of all jobs in the metro region are in the inner city areas, how can we ever expect to set targets much above that for public transit use? It’s a logical and mathematical improbability. 

It also means that the billions of dollars needed to upgrade public transit systems will only ever be able to serve the minority of the working population whose jobs are in locations capable of being served by public transport, based on current distribution of employment and the nature of transport networks. And it means that the majority who use private transport to reach their suburban workplaces would be unrealistic to expect the scale of infrastructure investment needed to de-congest the suburban road network. Fixing this conundrum means either a massive re-centralisation of employment around the CBD or achieving rates of population density across urban areas of Australia that are more likely to be found in Asian centres. Neither of which will happen soon. 

The other large, daily population movement around our cities, that of students, is obviously also very decentralised and thus not efficiently serviced by a CBD-centric transportation system. Plus, community wide changes of attitude about child safety have had a noticeable impact on the proportion of students who catch public transport, walk or cycle to school. by students.