How much of your area’s growth comes from ‘natural increase’?

Australia’s population is growing, but what is driving that growth? Natural increase, or the balance of births and deaths in a given area, is one cause of population change. In this blog, Glenn looks at the places in Australia that have the largest change in population from ‘natural increase’, including a map showing the strong spatial patterns associated with natural increase, which also allows you to see the effect of natural increase (or decrease) in your area.

We talk a lot about the growth of the Australian population, but that growth is the net effect of a few factors, which vary significantly from place-to-place. In this, the first in a three-part blog series, Glenn Capuano takes a closer look at natural increase as one component of population change.

Refresher: What are the causes of population change?

For the past three years, with the release of the current Estimated Resident Population figures, the ABS has given us an insight into the type of population change being experienced. They break population growth or decline into three categories, based on where the growth comes from;

Natural increase

This is growth through babies being born – or specifically, when there are more babies born than people who die, the population goes up. In some areas the reverse is true.

Overseas migration

This is growth due to immigration – or specifically, the excess of immigration over emigration – a lot of people forget the last bit, but people do leave Australia as well, so it’s “Net Overseas Migration” or NOM that we are talking about.

Internal migration

This is growth due to movement within Australia. This can be people moving to a neighbouring suburb, or all the way across the country. The population estimate uses things like Medicare change of address records to estimate how many people move in and out of a given area, to get a net figure for this as well.

All data in this blog are sourced from ABS, 3218.0, Regional Population Growth, 2017-18.

For this blog, we’re going to have a look at Natural increase in the 2017-18 financial year (and subsequent blogs in this series will look at the other types of growth).

Map: See the components of population change in your area

Every local government area has a different combination of these types of change. Have a look at the map to see what makes up the components of change for your area:

Search for your place, click the map + scroll to zoom in/out or click and drag to move the map

Which Local Government Areas have the largest natural increase in Australia?

The three columns showing % of total growth add to 100%, but not always in the way you might expect. Sometimes they are negative, and this tells you a lot about the area.

For instance, Canterbury-Bankstown, in NSW, has a large natural increase, accounting for 70% of their total growth. But at the same time, they lose about 72% of their total growth in migration elsewhere in Australia. The main gain here is overseas migration, which actually accounts for 102% of total growth!

Focusing on the natural increase, you can see, all these areas have substantially more births than deaths.

Brisbane is the number 1 area – mainly due to the very large population size here – it’s more than double the size of the next largest LGA, with 1.2 million people. But in percentage terms, growth is fairly well split between the 3 categories.

Very young first-home-buyer areas like Wyndham, Victoria, also have substantial natural growth – only 760 deaths here, and 4,822 births in a year. So even with no migration, it’s population would be going up by over 4,000 people per year. But you can see migration both within Australia and outside have a substantial contribution as well – which is why Wyndham is both the 3rd fastest and 3rd largest growing LGA in Australia.

• Most of those areas showing large natural increase are very large population areas, and also more likely to be outer suburban growth areas where couples move to buy homes and have children. Wyndham, Blacktown, Casey, Logan, and Hume all fall into this category.
• Brisbane, the ACT (which is really a territory and not an LGA) and Gold Coast all fall into the “very large” category.
• Cumberland and Canterbury-Bankstown, though quite large, aren’t really first home buyer areas. They do have very big migrant populations though, some of which have high birth rates.

Which Local Government Areas have the largest natural decrease in Australia?

This is possibly the more interesting list. A few things to notice about this one:

• The natural decreases are much smaller than the top increases in the table above. Australia is not Japan, and we still have a population mostly young enough to continue growing our population even in the absence of migration.
• 8 of the 10 areas with the greatest natural decrease would fall under the heading of “Coastal retirement areas”. ie. These are places, headed by Mid-Coast NSW (think Forster, Tuncurry), and Fraser Coast Qld (Hervey Bay) where people move when they retire, and stay there the rest of their lives. So people do eventually die, they don’t have many babies at that age, and the way these places grow is by importing more retirees.
• In fact, the coastal retirement areas all have increasing population (though not booming) – due to the large share of internal migration they get. Retirees come in and settle there on a regular basis.
• The other two areas in the list are Holdfast Bay and Unley. Both these are in Adelaide, and have substantially younger populations, but with a residual elderly population. Young people move there not to have kids, which is the same for many inner areas in our cities – but being South Australia, the residual elderly population tips them into a small negative natural increase. And you can see that in contrast to the other 8 in the list, most of their growth comes from overseas migration.

In which Local Government Areas does natural increase account for the greatest share of population growth?

These are mainly areas that have very small population growth, but their natural increase is positive – and often many times their total population growth.

Eg. Roxby Downs added 87 people through natural increase, but only had a population growth of 4, as many more people left the area in the last year (internal migration). These tend to be more remote areas with little population growth. The typical rural town has a slightly declining population due to people going elsewhere. Often young adults leave the area, but people are still having children and these areas may have many kids of school age, who leave to go to university.

On this list, only Belmont and Stirling are is in a metropolitan area (Perth). Stirling is, in fact, the only large-population LGA on the list. It has a population of over 220,000, and a large natural increase, with modest overseas arrivals in 2018. But it lost almost 3,000 people to internal migration within Australia. Not only are people moving interstate (in common with much of WA), but Stirling is an established area of Perth, so residents are moving outwards seeking more affordable housing in places like Wanneroo and Swan.

So natural increase is an important component of population growth, but in many areas, it’s a relatively small one. The next blog will look at overseas migration and areas that derive most of their growth from that.

Don’t forget, .id’s population forecasts give you all the components of population change for your area, forecast for the next 25 years, right on the website.

So you can see how your area is expected to change in the future. If you’re a growth area, you might be getting most of your growth from internal migration right now, but as the land supply wanes, more and more could come from natural increase in the future, with less opportunity for migration in. This is assessed suburb-by-suburb to give you the best understanding of the patterns of migration affecting your area.