Research Paper no. 8 2007–08
Electoral pendulum 2007
Statistics and Mapping Section
12 September 2007
Divisions to win after outcome of
- Since the 2004 election there have been electoral boundary
redistributions in the Australian Capital Territory (2005), New
South Wales (2006) and Queensland (2006).
- The 2004 election results have been transposed onto the new
boundaries and a revised electoral pendulum showing margins
(swings) needed to lose each division at the next election has been
produced (see Appendix).
- Notionally, there has been no change in the party
representation from the 2004 election outcome due to the 2005 and
2006 redistributions. However, it could be argued that the new
division of Calare is notionally a Coalition rather than
This Research Paper shows
the notional two-party preferred swing needed for each electoral
division (seat) to change hands at the next House of
Representatives election. The two-party preferred votes are the
results of the 2004 election adjusted for the effects of electoral
redistributions which occurred in the Australian Capital Territory
(ACT) during 2005, and New South Wales (NSW) and Queensland during
The redistribution in the ACT was triggered by
the passage of time a redistribution must be held in each state and
territory at least every seven years. There was no change in the
number of divisions resulting from this redistribution.
The NSW and Queensland redistributions were
triggered by a change in the two States entitlements to
representation in the House of Representatives in the 2005
determination by the Australian Electoral Commissioner. The
redistributions resulted in the creation of a new division, Flynn,
in Queensland and the abolition of Gwydir in NSW.
The 2005 redistribution in the ACT did not
change the notional party status of either of the two divisions.
Both the divisions of Canberra and Fraser remain Australian Labor
Party divisions. Canberra notionally increased its two-party
preferred margin by 0.3 per cent to 9.9 per cent and is now very
close to being classified as a safe seat.  Fraser s margin remained steady at 13.3
The 2006 redistributions resulted in NSW
losing a seat  the
northern, rural seat of Gwydir safely held by the Coalition
reducing its entitlement to 49 divisions, while Queensland
increased its entitlement to 29 seats with the creation of Flynn in
central Queensland.  The rural division of Flynn is notionally a fairly-safe
Coalition seat with a margin of 7.7 per cent.
Only two seats changed their notional party
status because of the redistributions; both in NSW. The inner
metropolitan Sydney seat of Parramatta changed from a marginal
Labor seat to a marginal Coalition seat, while the outer
metropolitan seat of Macquarie changed from a fairly-safe Coalition
seat to a marginal Labor seat.
The above outcomes result in a notional
composition of the House of Representatives before the next
election of 87 Coalition members, 60 Labor and 3 Independents for a
total of 150 members: unchanged from the actual position after the
2004 election. This gives the Coalition a majority of 24 seats in
the lower house. The Coalition would lose its absolute majority if
(net) 12 seats were lost at the next election. However, because of
the three Independent members, Labor would need to win an
additional (net) 16 seats to be able to form government in its own
A further issue to consider is the situation
in the independently held divisions of Calare and New England in
NSW and Kennedy in Queensland. The 2006 redistributions did not
result in any significant changes to the electoral boundaries in
either New England or Kennedy,  therefore, the current members who enjoy large
margins could reasonably be expected to retain their seats.
Calare, however, was substantially redrawn: 45
per cent of its voters were transferred to the seat of Macquarie.
In addition, its area was increased from 21 621 to
237 325 square kilometres by taking in a large part of old
Parkes to the Queensland border.
With the independent member for Calare, Peter
Andren, announcing in March 2007 that he was not standing for the
seat at the next election:
the effective abolition of the seat of Calare
with its splitting into two ... made that decision easier; 
it is feasible to suggest that Calare is now
notionally a Coalition seat on a two-party preferred basis, Calare
is a safe Coalition seat with a margin of 11.1 per cent.
Under this assumption, the notional
composition of the House of Representatives leading into the next
election is 88 Coalition members, 60 Labor and 2 Independents. This
means the Coalition would need to lose (net) 13 seats to lose its
absolute majority at the next election. The Labor party still needs
to win an additional (net) 16 seats to be able to win
The Appendix gives a table (commonly known as
a pendulum) of the two-party preferred margin (or swing) required
to lose each seat at the next election.  The seats are grouped in LP/NP
(Coalition), ALP (Labor) and Independent seats. Within the party
groupings, the seats are ranked from highest to lowest margin.
Based on the pendulum the ALP requires a
uniform two-party preferred swing of just over 4.8 per cent to gain
the necessary 16 seats to win government at the next election.
However, it is worth remembering that the
pendulum is not always an accurate predictor of which seats may be
lost and won because election swings are not necessarily uniform
across Australia, between States or even between regions. For
example, at the 2004 election the national two-party preferred
swing was 1.8 per cent to the Coalition. However, the swing in NSW
was only 0.3 per cent to the Coalition while in Western Australia
it was 3.8 per cent.
The 2005 and 2006 redistributions in the ACT,
NSW and Queensland have maintained a House of Representatives of
150 seats for the next election, although NSW lost a seat and
Queensland gained one.
The reworking of the 2004 election results
onto the new electorate boundaries, however, has not resulted in a
notional composition change between the parties in the House of
Representatives since the 2004 election; although, the major
redrawing of the boundaries of Calare may notionally have resulted
in an additional seat for the Coalition.
. Named in
honour of the Reverend John Flynn, founder of the Royal Flying
Doctor Service, Flynn stretches in a westward band from the port of
Gladstone to Winton.