How has the Australian Population grown and are we building enough?

The Australian population as been steadily increasing since 1985. There is only a small deviation in the trend in 2020 and 2021, due to the COVID-19 pandemic.
Meanwhile, the number of dwellings built has been fluctuating. There are surges in the number of homes being built, such as between 1992 and 1994, and between 2012 and 2017. These periods are followed by plummeting numbers of homes being built, such as between 1994 and 1997, and between 2017 and 2022.
While the two trend lines are on different scales, so they cannot be compared directly, we can see that the supply of new dwellings does not match the trend of the increasing population.

What have we been building?

We can also see that the types of homes built, and by who, has been changing over time. Note, the housing and other dwellings data has been smoother to remove seasonality and improve readability.
The number of houses being built has remained steady over time. Other types of dwellings, such as units and apartments, have been increasing.
The number of dwellings completed by the public sector has decreased since 1985. Only 732 dwellings were completed by the government in the September quarter of 2024 compared to 3772 in the September quarter of 1984.
On the other hand, the private sector has dramatically increased the number of dwellings being built. A high of 61,921 homes in the December quarter of 2016 is nearly double the figure of the December quarter of 1984 of 35,979. The private sector has since dropped off, but the December quarter 2024 figure of 48,484 still dwarves the amount of homes built by the government in that time.
While the number of homes built by the private sector has always out-paced the public sector, the gap between them is increasing. Given public sector housing usually aims to build affordable housing for lower socio-economic groups, this could be a key factor in the housing affordability crisis.

What about the value of what we are building?

Z-score standardisation has been used to allow for comparison between smoothed dwellings completed and the value of new residential builds. Therefore, 0 is the mean, -1 is one standard deviation below the mean, +1 is one standard deviation above the mean.
We can see that both lines follow an upward trend, however, there is a lot of variation over time. In particular, the number of dwellings built shows more variation than the value of new residential builds. This means that in some points in time, such as 1994 and 2017, there are more dwellings being built of lower value. While at other points in time, such as 2007 to 2012, and 2022, the opposite is true, fewer homes are being built and they are of higher value.
Although we can’t tell from this plot alone, this could be reflective of the state of the economy at the time. At some points, it is only wealthy people who can afford to build homes, so less houses are built, but they are of higher value. While at other times, the opportunity to build new homes is spread more evenly across the economy.

Lets compare the states

The values for dwellings completed have been smoothed to remove seasonality and to improve readability.

We can see a clear upward trend in the populations of the states. It is most pronounced in the three biggest states, New South Wales, Victoria and Queensland. They are closely followed by Western Australia. The other states have relatively flat populations, but they are still increasing.

We notice a large amount of variation in the number of dwellings completed per quarter, particularly among the four largest states. Interestingly, there is an obvious upward trend for all four states from around 2012 to 2018. After which, there is a significant drop off to about 2023. This upward and then downward trend is most severe in New South Wales. Meanwhile, Victoria has the smallest drop off in that period. This variability, and the recent drop off in the number of homes being built, could be contributing to the housing affordability crisis.

What are the four biggest states building at the moment?

Building by the private sector dominates any building done by the public sector. Western Australia has the highest proportion of houses built by the public sector at 656 compared to 19,985 by the private sector. Victoria has the worst proportion with 533 built by the public sector compared to 59,597 by the private sector.

The types of buildings built across the states is more even. New South Wales is the only state where the number of houses built is smaller than other dwellings. Western Australia has the highest number of houses built compared to other types of dwellings.

Variability across the states in the types of houses being built is expected, as the needs of the various states are different. The main area of concern is the very low number of houses built by the public sector, which would serve to relieve housing pressure on those most in need.

What does all this tell us?

Overall, the data paints a grim picture of the state of housing in Australia. While Australia’s population has consistently grown, the influx of new supply into the housing market has been variable. The recent decline in housing supply, which was particularly evident when looking at the four largest states, could be a strong contributing factor to the housing affordability crisis.

We also saw different trends between the supply of housing, and the value of that supply. This further contributes to the uneven way in which housing is built in Australia.

Furthermore, the decline of housing built by the public sector could be exacerbating housing affordability problems for lower socio-economic groups.

Although this data exploration cannot point to the causes of these trends, it does provide a platform for further work on the housing crisis.

References

1. Australian Bureau of Statistics. (2025, April 16). Population - states and territories [Data Set] https://www.abs.gov.au/statistics/people/population/national-state-and-territory-population/sep-2024#data-downloads

2. Australian Bureau of Statistics. (2025, April 16) TABLE 10. Value of Building Work Done, States and Territories - Chain Volume Measures: Original [Data set]. https://www.abs.gov.au/statistics/industry/building-and-construction/building-activity-australia/latest-release

3. Australian Bureau of Statistics. (2025, April 16) TABLE 39. Number of Dwelling Unit Completions by Sector, States and Territories: Original [Data set]. https://www.abs.gov.au/statistics/industry/building-and-construction/building-activity-australia/latest-release