Redistribution

2024 Federal Redistributions – Final Boundaries for NSW Released

(22 November – I’ve been through and finalised the split and merged SA1s to produce my final version of the margins. They have been incorporated into the table inside the post.)

(UPDATE – the final boundaries have been released confirming the abolition of North Sydney. There are some very minor changes of at most 0.1% and these have been updated in the table.)

(UPDATE – Friday 13 September – a discrepancy where the new electorate file coded Mcmahon rather than McMahon caused an error in my calculations. The significant changes are that Blaxland drops back from 13.9% to 13.1% while the new margin for McMahon is now 10.5% as opposed to the original estimate of 13.1%. There is also a minor adjustment for Fowler.

On Thursday 12 September, the Redistribution Committee for New South Wales released the final version of the state’s new Federal electoral boundaries. Draft boundaries were released in June and opened for public comment. This final version will be formally gazetted later this month and used for the first time at next year’s Federal election.

The redistribution has taken place to decrease the number of NSW federal divisions from 47 to 46. The final boundaries have confirmed the abolition of the Independent held seat of North Sydney.

The draft boundaries were released when I was overseas so this post is my first analysis of the draft boundaries. Today’s release includes a string small number of minor adjustments to the draft boundaries, none of which alter the analysis in this post. I will make minor adjustments to this post once the AEC publishes the datafiles required for calculations, sometime next month.

Re-calculating margins is a complex task of processing AEC polling place data files on where people voted in 2022 and comparing them with Bureau of Statistics files listing the low level SA1 (Statistical Area 1) composition of new electorates. Complicating the process is a re-numbering of many SA1s between the 2016 and 2021 Censuses. The 2022 AEC files used the old SA1 identifiers and the new electorate files use the new SA1 identifier. This has required a lot of fiddling with data to resolve inconsistencies between SA1 identifiers. Not all of the SA1 inconsistencies could be resolved but I do not believe they significantly affect any calculations.

The AEC will release its own versions of new margins next year as the election approaches. The AEC has many more resources to resolve SA1 inconsistencies and splits than are available to me.

Change in Seat Numbers

Change in Seats Held by Party
ALP LIB NAT GRN IND Total
Old boundaries 26 9 7 .. 5 47
New boundaries 25 10 7 .. 4 46

Based on traditional two-party preferred results, including for the underlying Labor-Coalition nature of Independent held seats, the changes in two-party preferred holdings are –

  • Old Boundaries 2PP: Labor 27, Coalition 20 (Liberal 13, National 7)
  • New Boundaries 2PP: Labor 26, Coalition 20 (Liberal 13, National 7)

The changes are brought about by the abolition of Independent-held North Sydney, a flow on impact of which is to flip neighbouring Bennelong from being a marginal Labor seat to as very marginal Liberal seat.

The three-way carve up of North Sydney along council boundaries is shown in the map below.

The main political implications of the changes are –

  • A relative decline in enrolment on Sydney’s lower north shore and northern beaches suburbs required a seat to be abolished north of the harbour, and as predicted before the process began, North Sydney has been abolished and divided between the re-drawn seats of Bennelong, Bradfield and Warringah.
  • There was also a shortfall south of the harbour but this has been fixed by a shift west and south-west of all boundaries to absorb a significant surplus of enrolments in south-west Sydney.
  • The Liberal electorate of Hume has also become an urban seat, shedding almost of all of its rural areas along the Hume Highway north of the ACT. It is now based on Camden in Sydney’s outer south-west fringe, along with western Parts of Liverpool Council and semi-rural Wollondilly Shire to the south. Geographically the changes are massive but the Liberal margin declines only slightly, from 7.7% to 6.9%.
  • The abolition of North Sydney is bad new for Independent Kylea Tink, but neighbouring Independents Sophie Scamps in Mackellar and Zali Staggall in Warringah retain their margins. There are few changes to the boundaries the western Sydney seat of Fowler won by Independent Dai Le in 2022.
  • In Wentworth, Independent Allegra Spender is significantly strengthened. Wentworth is a traditional Liberal seat but surrounding by Labor voting territory. By expanding into neighbouring Sydney and Kingsford Smith, Wentworth’s underlying Liberal 2-party preferred margin declines from 5.9% to 1.2%. Estimating a new Independent margin for the areas added to the seat is difficult, but a best estimate is that the addition of areas with weaker Liberal support boosts the Independent margin from 4.2% to 6.6%.
  • In Bradfield, Liberal MP Paul Fletcher faced a significant Independent challenge in 2022 that reduced his margin to just 4.2% versus an Independent. By shifting south and picking up parts of North Sydney, his margin is reduced to 2.5%. His Independent challenger from 2022, Nicolette Boele, has already announced she will contest the next election. It is unclear whether Kylea Tink will also contest Bradfield if the final boundaries confirm the abolition of her seat.
  • As already mentions, the abolition of North Sydney turns Bennelong from a marginal Labor seat to a very marginal Liberal sea.
  • By losing its Labor-voting southern end and extending north of Windsor Road, Michelle Rowland’s Labor seat of Greenway has its margin cut from 11.5% to an estimated 8.1%. As has been shown in the past, if the Liberal Party can select a good candidate, Greenway is a more marginal seat than it often appears on paper.
  • The Liberal margin for Hughes is cut from 7.0% to 3.6% as it loses Liberal voting areas near Sutherland and is pushed west beyond the Georges River to gain Labor voting territory from Weriwa and Macarthur. (There may changes to the construction of Hughes in the final boundaries.) There were no changes with the final boundaries.
  • In the Hunter valley, the transfer for Kurri Kurri strengthens Labor in Hunter but weakens its position in Paterson.
  • The National margin in Riverina declines from 14.8% to a still safe 9.7% after picking up parts of Eden-Monaro and Hume.

The new margin estimates in this post have not taken into account the adjustments included in the final boundaries. However, the list of adjustments released seem unlikely to change the estimated margins below.

Seat tables can be found inside the post.Read More »2024 Federal Redistributions – Final Boundaries for NSW Released

2024 Federal Redistributions – Final Boundaries for Victoria Released

(20 November – the tables in this post have been updated taking account of the final boundaries and incorporating split and merged SA1s. The complex way that final descriptions are released has made it difficult for me to update the transfers listed in the table but the margins have been updated.)

(Updated Friday 6 September with maps and more details on Chisholm, Deakin, Goldstein, Kooyong, Melbourne, Menzies and Wills. Estimated margins for Independent contests will be added later today..)

On Thursday 5 September the Redistribution Committee for Victoria released the fin al version of the state’s new Federal electoral boundaries. Draft boundaries were released in May and opened for public comment. This final version will be formally gazetted later this month and used for the first time at next year’s Federal election.

The redistribution has taken place to decrease the number of Victorian federal divisions from 39 to 38. The final boundaries have confirmed the abolition of the Labor seat of seat of Higgins in inner-eastern Melbourne.

Today’s release has included a string of minor adjustments to the draft boundaries, none of which appear significant to me. The release does not include the datafiles that permit new margins to be calculated. I won’t update the margins shown inside this post until the datafiles are released.

Re-calculating margins is a complex task of processing AEC polling place data files on where people voted in 2022 and comparing them with Bureau of Statistics files listing the low level SA1 (Statistical Area 1) composition of new electorates. Complicating the process is a re-numbering of many SA1s between the 2016 and 2021 Censuses. The 2022 AEC files used the old SA1 identifiers and the new electorate files use the new SA1 identifier. This has required a lot of fiddling with data to resolve inconsistencies between SA1 identifiers.

In my analysis of the draft boundaries in May I had to manually resolve these problems. I’ve managed to code the corrections this time though there are still a few inconsistencies that can’t be resolved by me. A number of the margins in this post have altered since May using the better correction method. The AEC will eventually release their own versions of new margins in the new year and they have a lot more resources than me to resolve SA1 inconsistencies and splits.

What this post does not yet do is take into account the adjustments in the final release of boundaries. I can’t do these calculations until the AEC release the maps and data files.

I have also not added estimated margins for a couple of Independent seats. That requires some manual re-calculations that I will do later today.

Change in Seat Numbers

Change in Seats Held by Party
ALP LIB NAT GRN IND Total
Old boundaries 24 8 3 1 3 39
New boundaries 24 7 3 1 3 38
With by-elections 25 6 3 1 3 38

Note: By-election line takes account of Labor winning Aston from the Liberal Party at an April 2023 by-election. Table does not take account of the decision by Monash MHR Russell Broadbent to resign from the Liberal Party and become an Independent.

Based on the two-party preferred results, including the underlying Labor-Coalition nature of Independent and Greens held seat, the changes in two-party preferred holdings are –

  • Old Boundaries 2PP: Labor 25, Coalition 14 (Liberal 11, National 3)
  • New Boundaries 2PP: Labor 25, Coalition 13 (Liberal 10, National 3)
  • Including by-elections: Labor 26, Coalition 12 (Liberal 9, National 3)

The main political implications of the changes are –

  • The Labor seat of Higgins is abolished.
  • Labor’s position in Wills is significantly weakened with the inclusion of strong Greens voting areas around Brunswick East, Carlton North and Fitzroy North. The Labor margin versus the Greens is reduced from 8.6% to an estimated 4.6%.
  • The transfer of strong Labor voting areas to Menzies, replaced by marginal Liberal country from Higgins and Kooyong, weakens Labor’s position in Chisholm, an estimated halving of the Labor margin from 6.4% to 3.2%.
  • The Liberal marginal seats of Deakin and Menzies in eastern Melbourne become even more marginal with Menzies flipping to become a notional Labor seat.
  • The strongest Liberal voting parts of Higgins have been transferred to Kooyong, held by Independent MP Dr Monique Ryan. Estimating support for an Independent in areas they did not contest at the last election, but my best estimate is that Ryan’s margin is reduced from 2.9% to 1.8%.
  • The boundary changes for Goldstein are estimated to increase the margin of Independent Zoe Daniel from 2.9% to 3.1%.

None of the estimates in this post take account of the changes announced with the release of the final boundaries. I do not believe that any of the final changes have much impact on marginal seats.

Seat tables can be found inside the post.Read More »2024 Federal Redistributions – Final Boundaries for Victoria Released

2024 Federal Redistribution – Final Boundaries for Western Australia Released

Update Tuesday 24 September – the redistribution has been finalised and all maps and data released.

Update Friday 22 November – I took a fine toothed comb to SA1s that were split or merged in the redistribution and have re-calculated margins. No major changes and the final estimates have been included in the table.

On Thursday 5 September, the Redistribution Committee for Western Australia released the state’s new Federal electoral boundaries. Draft boundaries were released in May and opened for public comment. This final version will be formally gazetted later this month and will be used for the first time at next year’s Federal election.

The redistribution has taken place to increase the number of WA federal divisions from 15 to 16.

The original post follows.

A new division called Bullwinkel has been created covering Perth’s outer east and the rural Avon Valley to the east. A map of the new electorate is included in this post. The name Bullwinkel honours Lieutenant Colonel Vivian Bullwinkel AO MBE ARRC ED FNM FRCNA (1915–2000), a civilian and military nurse who was the sole survivor of the 1942 Bangka Island massacre and a prisoner of war. The name recognises her dedication to honouring victims of war crimes, service to nursing, and the community, in both her civilian and military service. This electoral division name also honours the contribution of military medical personnel and recognises those who were prisoners of war.

The final boundaries have been released and involve only minor changes. These are –

  • Waroona Shire remains in Canning where the draft moved it into Forrest.
  • The suburb of Malaga remains in Cowan having originally been proposed for transfer to Hasluck.
  • Part of Kardinya remains in Fremantle after having been proposed for transfer to Tangney.
  • Part of Leeming proposed to be in Fremantle is now in Tangney.

These are very minor changes and the data files required to re-calculate margins will not be available for several weeks. I will update the post when they are available.

At this state the page and its included tables reflect the draft boundaries released earlier this year. I have noted where there are changes but doubt these will have any significant impact on the estimated new margins shown.

The political implications of the boundaries are –

  • The new seat of Bullwinkel is a notional Labor seat using the unusually good Labor results at the 2022 federal election. At a more normal election, and without a sitting member, Bullwinkel will be very difficult seat for Labor to notionally retain.
  • The creation of Bullwinkel results in a significant strengthening of Labor’s position in Hasluck, the Labor margin increasing from 6.0% to 10.0%.
  • Curtin sees only a minor change to boundaries meaning the redistribution has no impact on Liberal attempts to defeat Independent Kate Chaney.
  • Labor’s other marginal seats see only minor changes, Pearce’s Labor margin now 8.8%, Swan 9.4% and Tangney 2.9%.
  • On paper the Liberal margin in Canning is reduced to 1.1% but sitting MP Andrew Hastie would only be in trouble if Labor had an increase in its vote compared to 2022, a scenario that does not seem likely.
  • Moore remains a marginal seat, but less important than the redistribution is Ian Goodenough being replaced as Liberal candidate by Vince Connelly. If Goodenough were to re-contest as an Independent or National Party (one rumour) candidate, it would create a more complex contest.
Change in Seats Held by Party
Labor Liberal Independent Total
Old boundaries 9 5 1 15
New boundaries 10 5 1 16

Based on the two-party preferred results, including the underlying Labor-Coalition nature of the Independent held seat of Curtin, the changes in two-party preferred holdings is –

  • Old Boundaries 2PP: Labor 9, Liberal 6
  • New Boundaries 2PP: Labor 10, Liberal 6

Tables summarising the impact of the redistribution on each seat is included inside the post.
Read More »2024 Federal Redistribution – Final Boundaries for Western Australia Released

Draft South Australian Electoral Boundaries Released

The South Australian Electoral Districts Boundaries Commission (EDBC) has this morning released its draft version of new state electoral boundaries. The draft boundaries are open for comment and will be finalised later this year.

The EDBC’s home page for the redistribution can be found here.

I’m a bit busy with Northern Territory election preparation so don’t have much time to offer comment. Helpfully the EDBC is the only redistribution authority in Australia that releases estimated margins for new seats.

Here’s what I find the most noteworthy points in the EDBC report.
Read More »Draft South Australian Electoral Boundaries Released

Proposed Federal Electoral Boundaries Released for Western Australia

The Australian Electoral Commission (AEC) will release draft electoral boundaries for Western Australia on Friday, the time provisionally set for lunchtime AEST. Western Australia will be gaining a seat in the redistribution, the number of members to be elected at the next election increased from 15 to 16 seats.

Once the draft boundaries are released I’ll give a brief comment on the newly created seat, but it will take time and some serious number crunching to work out the full consequences of the new boundaries.

I’ve now double checked every discrepancy and my figures are final.

The major changes are that the new seat of Bullwinkel is a marginal Labor seat, Hasluck is made safer for Labor and Canning is made more marginal for the Liberal Party.

The new electorate is named in honour of Lieutenant Colonel Vivian Bullwinkel AO MBE ARRC ED FNM FRCNA (1915–2000), a civilian and military nurse who was the sole survivor of the 1942 Bangka Island massacre and a prisoner of war. The name recognises her dedication to honouring victims of war crimes, service to nursing, and the community, in both her civilian and military service. This electoral division name also honours the contribution of military medical personnel and recognises those who were prisoners of war.

The table below of seats held by party will be updated during my various parses of the data.

Change in Seats Held by Party
Labor Liberal Independent Total
Old boundaries 9 5 1 15
New boundaries 10 5 1 16

Based on the two-party preferred results, including the underlying Labor-Coalition nature of the Independent held seat of Curtin, the changes in two-party preferred holdings are –

  • Old Boundaries 2PP: Labor 9, Liberal 6
  • New Boundaries 2PP: Labor 10, Liberal 6

A seat table comparing margins can be found inside the post.Read More »Proposed Federal Electoral Boundaries Released for Western Australia

Proposed Federal Boundaries Released for Victoria

The Australian Electoral Commission (AEC) will release draft electoral boundaries for Victoria today, the time set as some time between 12:30 and 2:30. Victoria will be losing a seat in the redistribution, the number of members to be elected reduced from 39 to 38 seats.

Once the draft boundaries are released I’ll give a brief comment on which seat has been abolished, but it will take time and some serious number crunching to work out the full consequences of the new boundaries.

Update 7pm Friday After fixing problems with a changed numbering system for SA1s, I’ve tidied all the estimates. The summary is that the Labor seat of Higgins is abolished but the Liberal seat of Menzies becomes a marginal Labor seat. The Liberal seat of Deakin is weakened for the Liberal Party and Wills is weakened for Labor in a contest versus the Greens.

The Greens versus Labor margin for Melbourne is not right but I don’t have time work out the problem tonight. A better estimated margin has now been calculated for Melbourne. Other independent contests now have better estimated margins.

** Sunday update on Kooyong The re-drawn seat of Kooyong includes around 30,000 voters from the abolished seat of Higgins. This is around a quarter of the voters in the re-drawn Kooyong. This is an area where Independent Monique Ryan was not on the ballot paper in 2022 and if you do a straight vote transfer and then apply preferences, you get an Independent v Liberal margin of 0.8%, down from 2.9%. This is not a realistic margin as clearly Monique Ryan will attract votes in the area added from Higgins.

Compared to the 2022 Liberal 2PP margin versus Labor, the new boundaries produces a slight dip in the Liberal margin versus Labor. I suspect that movement slightly improves Ryan’s margin versus the Liberal Party, but there is no way to calculate a margin without coming up with an estimate of how Ryan will poll in the transferred parts of Higgins where she was not on the ballot paper in 2022.

I’ve removed my earlier margin from the table below because it is being quoted as suggesting the Liberal position in Kooyong has been significantly improved. That is not my opinion.

** Sunday update on Goldstein I’ve removed the estimated Independent margin for Goldstein for the same reasons. Transferring votes and re-calculating preferences gives a new Independent v Liberal margin of 2.7%, down from 2.9% on the old boundaries. The changes to Goldstein are smaller than for Kooyong. The Liberal 2PP margin dips on the new boundaries and I think the same may apply to the Independent versus Liberal margin.

Change in Seat Numbers

The table below of seats held by party will be updated during my various parses of the data.

Change in Seats Held by Party
ALP LIB NAT GRN IND Total
Old boundaries 24 8 3 1 3 39
New boundaries 24 7 3 1 3 38
With by-elections 25 6 3 1 3 38

Note: By-election line takes account of Labor winning Aston from the Liberal Party at an April 2023 by-election. Table does not take account of the decision by Monash MHR Russell Broadbent to resign from the Liberal Party and become an Independent.

Based on the two-party preferred results, including the underlying Labor-Coalition nature of Independent and Greens held seat, the changes in two-party preferred holdings are –

  • Old Boundaries 2PP: Labor 25, Coalition 14 (Liberal 11, National 3)
  • New Boundaries 2PP: Labor 25, Coalition 13 (Liberal 10, National 3)
  • Including by-elections: Labor 26, Coalition 12 (Liberal 9, National 3)

Seat tables can be found inside the post.Read More »Proposed Federal Boundaries Released for Victoria

Update on looming elections, by-elections and redistributions

March will be a big month for elections. It’s keeping me very busy.

The biggest election in terms of voter numbers is Brisbane City Council, followed by the Tasmanian state election.

There is also a Federal by-election in Dunkley, two Queensland state by-elections and one South Australian state by-election.

Over the horizon beyond Easter are the Cook federal by-election, and now an announcement on the start to the Northern Territory federal redistribution.

I have ABC websites and blog posts being updated on all these electoral events. This post is an opportunity to highlight the on-going work I’m doing on each of these events, as well as pointing out some of the most recent updates.Read More »Update on looming elections, by-elections and redistributions

Redistribution begins for Northern Territory Federal Boundaries

Today marks seven years since the Northern Territory’s current federal electoral boundaries were first gazetted. Under the ‘seven-year rule’ in Section 59 of the Commonwealth Electoral Act, a redistribution of the NT’s federal boundaries must commence within 30 days.

The NT’s redistribution will differ from those currently underway in New South Wales, Victoria and Western Australia. The other state redistributions have been triggered by a change in seat entitlements under Section 24 of the Constitution. New South Wales and Victoria will both lose a seat, Western Australia gain a seat. The seat numbers will be unchanged at two for the NT redistribution.

Seven-year rule redistributions can be deferred if they commence within twelve months of the expiry date for the House of Representatives. The deferral deadline in 2024 is May, meaning seven-year rule redistributions due for Tasmania in November and Queensland in March 2025 will be deferred until after the next election.

But the Northern Territory redistribution will go ahead. With only two seats involved, the process of drawing boundaries will be easily completed before the next election is due. Unlike with change of seat number redistributions, there are no complications if an early election is called because the existing NT divisions would remain in place.

While unlikely to have major political implications, it is worth looking at the NT redistribution to examine how the NT briefly lost its second seat in 2020, and also to observe how the Australian Electoral Commission’s Indigenous enrolment drive before the 2023 referendum has increased remote enrolment.
Read More »Redistribution begins for Northern Territory Federal Boundaries

Victorian Federal Redistribution using Updated Enrolment Data

Last October, eagle eyed observers spotted that there was something wrong with enrolment projection data for Victoria released by the Australian Electoral Commission (AEC). The projections were released as base data for the looming federal redistribution to remove one of Victoria’s 39 seats in the House of Representatives.

A 2023 decision by the Australian Electoral Commissioner under Section 24 of the Constitution had determined that NSW and Victoria would lose House seats and Western Australia gain a seat. The size of the House of Representatives for the next election will be reduced from 151 to 150 seats. I wrote a post at the time explaining the decision.

Victoria had gained an extra seat at each of the two previous elections. Both had been created in western Melbourne, Fraser before the 2019 election and Hawke ahead of 2022. The redistribution creating Hawke had been based on population data from before the 2020 arrival of Covid. With overseas immigration halted for two years, and internal migration to the outer states continuing, Victoria’s population declined relative to other states over the three intervening years.

But removing a seat won’t simply be a matter of abolishing Hawke or Fraser. As the projected enrolment data released last week shows, population growth in Melbourne’s north and west is faster than in Melbourne’ east and south-east. A seat must be abolished in Victoria and the corrected projected enrolment data indicates strongly that a seat will be abolished in Melbourne’s east.

The first projected enrolment data released last October had been prepared by the Australian Bureau of Statistics (ABS) for the Australian Electoral Commission (AEC). The data was flawed in applying a uniform growth rate across the state. The corrected enrolment projections released by the AEC last week now have growth rates that vary across the state.

(Happy to post comments with people’s suggestions on where the changes will occur.)
Read More »Victorian Federal Redistribution using Updated Enrolment Data

WA Federal Redistribution Prospects using Updated Enrolment Data

Last October, eagle eyed observers spotted that there was something wrong with enrolment projection data released by the Australian Electoral Commission (AEC). The data had been released as base data for redistributions in Victoria and Western Australia. Data for the NSW redistribution was not affected.

The same enrolment growth rate had been applied across both states down to local statistical area level. This was a ridiculous assumption. It turned out the Australian Bureau of Statistics (ABS) had provided the Australian Electoral Commission (AEC) with the wrong data.

In the last few days the has AEC released corrected enrolment projections with growth rates that vary across both states. This post examines how this new data will influence the redistribution in Western Australia. A second post, hopefully tomorrow, will run through a similar analysis for Victoria.

In a previous post I explained why the seat numbers by state are changing. Another post, now superseded by the post you are reading, looked at boundary change implications from last October’s initial release of incorrect enrolment projections.

What doesn’t change is that Western Australia is gaining a seat in the current redistribution, restoring the 16th seat removed three years ago. Population trends mean the new seat will be created in a different part of Perth than the previously abolished seat of Stirling.

In short, the projected enrolment data makes even clearer that WA’s new seat will be created in Perth’s east. The other 12 Perth seats will shuffle west towards the Indian Ocean. Current enrolment data, and last October’s incorrect projected enrolments, indicated that a Perth seat would need to cross the metropolitan boundary. The new projections remove this prospect meaning the redistribution will be largely confined to metropolitan Perth.Read More »WA Federal Redistribution Prospects using Updated Enrolment Data