The young and the old - how age structures differ across NSW

Recently I published a blog that looked at the importance of considering age alongside other social variables in order to give it more context.  This blog will continue the age theme, but look at examples of different age structures across NSW.  The data is sourced from the ABS release Regional Population by age and sex (ABS Cat. no. 3235.0) and as such uses the 2017 ERP (Estimated Resident Population - the official figure) rather than the Census figure.

What is the age structure of NSW?

NSW is currently experiencing a strong rate of population growth - 1.5% for the year ended December 2017.  This is partly due to increased levels of net overseas migration.  As a global city, Sydney attracts a disproportionate share of Australia's migration intake, so when net overseas migration is high, it tends to have a positive effect on Sydney's growth rate.  

The age structure of NSW in 2017 (June 30) is shown in the graph below.  You can see the impact of overseas migration with a larger cohort of 25-34 year olds.  Furthermore, the larger size of the 0-9 years cohort compared to 10-19 years shows the impact of higher birth numbers in recent years.  At the other end of the age spectrum, around 2% of the population, or almost 170,000 people, are aged 85 years and over.

Not all areas in NSW have this age structure.  This is because different places vary with respect to their role and function, and they also developed and have evolved differently over time.  The rest of this blog will look at three areas in NSW, how their age structures differ and what this means for service planning.

Young area - Camden

Camden is located in the outer south west of the Sydney metropolitan area.  The SA3 covers part of the LGA of the same name.  Though the area was settled by Europeans as early as the 1790s, it has recently become one of the fastest growing areas in Australia.  Camden has a large supply of new residential land and new suburbs such as Spring Farm are providing relatively affordable home owning opportunities for young families.  The age structure of Camden SA3, and how it compares to NSW, is shown below.  

Clearly, the proportion of children, teenagers and middle aged adults is higher than NSW.  Almost one-third of the Camden SA3 population is aged 0-19 years, compared to one-quarter of the NSW population.  However the proportion of persons aged 50 years and over is much lower than NSW.  The rapidity of recent growth in predominantly family age groups has skewed the age structure towards the bottom end of the spectrum.

Young populations are typically found in greenfield areas on the urban fringe as they are attractive to first home buyers.  Other examples include Blacktown and Penrith.  A critical issue for planning in these areas is how to service the school population.  A recent news article highlighting the issues on Melbourne's western fringe are no doubt reflected in other areas and show the importance of understanding age structures and how they change over time.

Youngish area - Sydney Inner City

Inner cities have long attracted young adults and despite housing affordability issues they remain sought after places to live.  This is in no doubt due to the proximity to employment markets and education institutions, but also the life style opportunities on offer.  Sydney Inner City encompasses the CBD and surrounds.  The age structure and how it compares to NSW is shown below.

The salient feature here is the very high proportion of young adults in Sydney Inner City.  Almost half the population is aged 20-34 years, compared to 22% in the NSW population.  However the proportion of children and teenagers (0-19 years) is much lower - 11% in Sydney Inner City compared to almost 25% in NSW.  Older age groups are also underrepresented in the Sydney Inner City population with less than 2% aged 80 years and over.  

Inner city areas, and areas with universities tend to have high proportions of young adults, especially 20-24 year olds as this cohort covers much of the study body.  Other examples of areas with these populations include Armidale (University of New England), Ryde (Macquarie University) and Wollongong (University of Wollongong).  

Old area - South Coast

The South Coast SA3 stretches from Batemans Bay down to Eden and the Victorian border.  It encompasses a number of coastal towns and essentially covers the LGAs of Eurobodalla and Bega Valley.  Both these LGAs have grown strongly in the past on the back of retirement and amenity migration, particularly during the 1980s and 1990s.  In more recent years growth has been modest, but they still attract retirees and a process of ageing in place means that the age structure is much older.  

The age structure of South Coast SA3 and the comparison to NSW is shown below and the older age structure is very clear.  More than half of the South Coast SA3 population is aged 50 years or over compared to one quarter of the NSW population.  The difference is more pronounced for the peak retirement migration age groups of 55-74 years - 34% of the South Coast SA3 population falls into this cohort.

However the lower proportion of young adults and persons in their thirties is also an important feature of the age structure.  This then translates into fewer children and teenagers.  Like much of regional Australia, young adults on the NSW South Coast tend to move elsewhere once they finish school and this impacts the age structure.  Just 7% of the South Coast SA3 population are aged in their twenties, compared to 14% for NSW.

Much of the NSW coast outside large cities is attractive to retirement migrants and as such many have older populations.  The stretch of coastline between Newcastle and Tweed Shire is similar to the South Coast SA3.  However older age structures are also a feature of much of inland NSW.  However these areas typically do not attract retirees, so their older populations are more a function of the out migration of young adults and minimal (if any) population growth.

What are the implications of different age structures?

In addition to service planning implications, so too is an understanding of the age structure and how it's changing.  From a state and local government perspective, a large proportion of services are age related so critical decisions around community infrastructure are important to budgets.  Child care, kindergartens and aged care facilities are examples of these.

From a demographic perspective, age structures have inbuilt momentum, so can determine the size and composition of the population in the future.  For instance, it's difficult for older populations to grow through natural increase simply because older people don't have babies.  I made this point recently in the blog about the Yorke Peninsula.  Because most deaths occur at older age groups, the balance between births and deaths is tipped in favour of the latter.  Natural decrease is a common outcome and when this occurs the only way a population can grow is through net in-migration.  Conversely, areas with large proportions of young adults, particularly those in couples and families, indicate a future with higher proportions of young children.

Summary

The population of NSW is currently growing at a strong rate, in part due to higher levels of net overseas migration.  However growth is not, and has never been, distributed evenly across NSW.  This, in tandem with differing roles and functions of areas, means that the age structure also differs widely.  It is important to have an understanding of the age structure, particularly from a service provision, but it also provides clues as to how populations may grow in the future.