Evolving Australia's Consumer Price Index

How the collection and publication of prices in Australia has evolved from the early 1900s to the monthly CPI Indicator and the complete Monthly CPI

Released

29/10/2025

Source

Consumer Price Index, Australia, September Quarter 2025

Monthly Consumer Price Index Indicator, September 2025

Released

29/10/2025 11:30am AEDT

Introduction

The Consumer Price Index (CPI) is one of the longest time series produced by the Australian Bureau of Statistics (ABS). With prices collected since the early 1900s the CPI has been through many changes over the decades as it evolved to meet Australia’s changing information needs.

This month marks another significant step in the life of Australia’s CPI with the final publication of the monthly CPI Indicator, and the last release of the quarterly CPI as the primary measure of headline inflation. The ABS will be transitioning to a complete monthly measure of the CPI as Australia’s primary measure of headline inflation on 26 November 2025 (for the October reference month).

A History of Change

Australia’s first Commonwealth Statistician, Sir George Knibbs commenced work to introduce an index to measure price changes in Australia in 1910. At the time, the Commonwealth Bureau of Census and Statistics (as the ABS was then known) said:

‘Probably no subject has recently attracted a greater amount of public attention than the extent of variations in prices and the exchange-value of gold, a matter which, in its relation to the cost of living, is fraught with importance to every section of the community’.¹

Prescient words indeed as the importance of, and fascination with, variations in the price of products bought by Australians continues to this day.

Looking at how changes in prices have tracked in relation to major world and economic events demonstrates why this interest is well placed.

Annual CPI movement (%)
	RBA inflation target of 2-3%	Annual CPI Movement (%)
1950		7.7
1950		7.5
1950		7.3
1950		12.2
1951		14.3
1951		18.6
1951		20.5
1951		23.9
1952		22.9
1952		19.6
1952		17
1952		10.5
1953		6.8
1953		4.9
1953		4.8
1953		1.6
1954		3.2
1954		1.6
1954		0
1954		1.6
1955		0
1955		1.5
1955		1.5
1955		3.1
1956		3.1
1956		6.1
1956		7.6
1956		6
1957		6
1957		2.9
1957		1.4
1957		1.4
1958		1.4
1958		0
1958		0
1958		1.4
1959		1.4
1959		1.4
1959		2.8
1959		2.7
1960		2.7
1960		4.1
1960		4.1
1960		4
1961		4
1961		3.9
1961		1.3
1961		0
1962		0
1962		-1.3
1962		0
1962		0
1963		0
1963		0
1963		1.3
1963		1.3
1964		2.6
1964		2.6
1964		2.5
1964		3.8
1965		2.5
1965		3.8
1965		3.7
1965		3.7
1966		4.9
1966		3.6
1966		2.4
1966		2.4
1967		2.3
1967		3.5
1967		4.7
1967		3.4
1968		3.4
1968		2.2
1968		2.2
1968		2.2
1969		3.3
1969		3.3
1969		3.3
1969		3.3
1970		2.1
1970		3.2
1970		3.2
1970		5.3
1971		5.2
1971		5.2
1971		7.1
1971		7
1972		6.9
1972		6.9
1972		5.7
1972		4.7
1973		5.6
1973		8.3
1973		9.9
1973		12.5
1974		14
1974		14.4
1974		16.4
1974		16.7
1975		17.7
1975		17
1975		12
1975		14.3
1976		13.1
1976		12
1976		13.8
1976		14.3
1977		13.3
1977		13.6
1977		13.3
1977		9.4
1978		8.7
1978		8
1978		7.8
1978		7.6
1979		8
1979		8.8
1979		9.5
1979		10.2
1980		10.4
1980		11
1980		9.9
1980		9.2
1981		9.4
1981		8.4
1981		9
1981		11
1982		10.8
1982		10.9
1982		12.4
1982		11.3
1983		11.4
1983		11.1
1983		9.2
1983		8.6
1984		5.8
1984		4
1984		3.7
1984		2.5
1985		4.4
1985		6.6
1985		7.6
1985		8.3
1986		9.2
1986		8.5
1986		8.8
1986		9.6
1987		9.4
1987		9.3
1987		8.3
1987		7.2
1988		6.8
1988		7.2
1988		7.3
1988		7.6
1989		6.8
1989		7.5
1989		8
1989		7.8
1990		8.7
1990		7.7
1990		6.1
1990		6.9
1991		4.8
1991		3.3
1991		3.1
1991		1.5
1992		1.7
1992		1.2
1992		0.8
1992		0.3
1993	2\|3	1.2
1993	2\|3	1.8
1993	2\|3	2.2
1993	2\|3	1.8
1994	2\|3	1.5
1994	2\|3	1.8
1994	2\|3	2
1994	2\|3	2.6
1995	2\|3	3.7
1995	2\|3	4.5
1995	2\|3	5.1
1995	2\|3	5.1
1996	2\|3	3.8
1996	2\|3	3.1
1996	2\|3	2.1
1996	2\|3	1.5
1997	2\|3	1.4
1997	2\|3	0.3
1997	2\|3	-0.4
1997	2\|3	-0.3
1998	2\|3	-0.1
1998	2\|3	0.7
1998	2\|3	1.4
1998	2\|3	1.5
1999	2\|3	1.2
1999	2\|3	1
1999	2\|3	1.8
1999	2\|3	1.9
2000	2\|3	2.8
2000	2\|3	3.1
2000	2\|3	6.1
2000	2\|3	5.8
2001	2\|3	6
2001	2\|3	6.1
2001	2\|3	2.5
2001	2\|3	3.1
2002	2\|3	3
2002	2\|3	2.8
2002	2\|3	3.2
2002	2\|3	2.9
2003	2\|3	3.3
2003	2\|3	2.6
2003	2\|3	2.6
2003	2\|3	2.4
2004	2\|3	2
2004	2\|3	2.5
2004	2\|3	2.3
2004	2\|3	2.5
2005	2\|3	2.4
2005	2\|3	2.5
2005	2\|3	3.1
2005	2\|3	2.8
2006	2\|3	2.9
2006	2\|3	4
2006	2\|3	4
2006	2\|3	3.3
2007	2\|3	2.5
2007	2\|3	2.1
2007	2\|3	1.8
2007	2\|3	2.9
2008	2\|3	4.3
2008	2\|3	4.4
2008	2\|3	5
2008	2\|3	3.7
2009	2\|3	2.4
2009	2\|3	1.4
2009	2\|3	1.2
2009	2\|3	2.1
2010	2\|3	2.9
2010	2\|3	3.1
2010	2\|3	2.9
2010	2\|3	2.8
2011	2\|3	3.3
2011	2\|3	3.5
2011	2\|3	3.4
2011	2\|3	3
2012	2\|3	1.6
2012	2\|3	1.2
2012	2\|3	2
2012	2\|3	2.2
2013	2\|3	2.5
2013	2\|3	2.4
2013	2\|3	2.2
2013	2\|3	2.7
2014	2\|3	2.9
2014	2\|3	3
2014	2\|3	2.3
2014	2\|3	1.7
2015	2\|3	1.3
2015	2\|3	1.5
2015	2\|3	1.5
2015	2\|3	1.7
2016	2\|3	1.3
2016	2\|3	1
2016	2\|3	1.3
2016	2\|3	1.5
2017	2\|3	2.1
2017	2\|3	1.9
2017	2\|3	1.8
2017	2\|3	1.9
2018	2\|3	1.9
2018	2\|3	2.1
2018	2\|3	1.9
2018	2\|3	1.8
2019	2\|3	1.3
2019	2\|3	1.6
2019	2\|3	1.7
2019	2\|3	1.8
2020	2\|3	2.2
2020	2\|3	-0.3
2020	2\|3	0.7
2020	2\|3	0.9
2021	2\|3	1.1
2021	2\|3	3.8
2021	2\|3	3
2021	2\|3	3.5
2022	2\|3	5.1
2022	2\|3	6.1
2022	2\|3	7.3
2022	2\|3	7.8
2023	2\|3	7
2023	2\|3	6
2023	2\|3	5.4
2023	2\|3	4.1
2024	2\|3	3.6
2024	2\|3	3.8
2024	2\|3	2.8
2024	2\|3	2.4
2025	2\|3	2.4
2025	2\|3	2.1
2025	2\|3	3.2

2020-23 Covid-19
2008-09 Global Financial Crisis
2000 Introduction of GST
1997 Asian Financial Crisis
1991 Recession
1982-83 Recession
1979-80 Second OPEC oil price shock
1973-74 First OPEC oil price shock
1950-51 'Korean War boom'
September 1960 CPI first Published, linked back to 1948
1960-61 Recession

Annual CPI movement (%)

["","RBA inflation target of 2-3%","Annual CPI Movement (%)"]

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The CPI itself has been through many reviews and enhancements over the years with major changes including:

Shifting from an index primarily designed to support wage and salary decisions to a more general measure of price inflation following the introduction of inflation targeting² by the RBA.
Expanding the population coverage of the CPI from wage and salary earner households to cover all private households in the eight capital cities. This resulted in the population coverage increasing from 29% to 64% of Australian private households.
Changing to an ‘acquisitions’ approach, which entailed excluding mortgage interest and consumer credit charges from the index (these indexes were later included in the Selected Living Cost Indexes which are produced on an ‘outlays’ basis and more closely approximate a measure of living costs).
The introduction of annual reweighting of the CPI basket using Household Financial Consumption Expenditure data from the National Accounts.³
Significantly broadening the range of products included in the ‘basket of goods’ that make up the CPI from 46 products in 1912 to thousands of products, underpinned by millions of price observations, today.⁴
Introducing larger and more robust datasets, including supermarket scanner data, into the CPI to replace price collection in stores by field officers.⁵
The introduction of the monthly CPI Indicator.⁶

The transition to a complete Monthly CPI is the latest in these evolutions and ensures that the CPI will continue to meet the contemporary information needs of policy makers, researchers and the public.

The Monthly CPI Indicator

In 2022, the ABS introduced the monthly CPI Indicator to offer timelier insights into inflation ahead of the headline quarterly CPI.⁷

Innovations, such as the introduction of scanner data into the CPI, had meant that around 50% of the CPI basket of goods and services was being collected monthly. When combined with other data being collected quarterly, this meant that there was a significant proportion of the basket with up-to-date prices each month (see Table1).

Table 1. Monthly Indicator by collection frequency (monthly, quarterly, or annual basis)
CPI for month of	Data updated monthly (%)	Data updated quarterly (%)	Data updated annually (%)	Prices not updated (carried forward) (%)	Total weight (%)
January, April, July, and October	50	9	9	32	100
February, May, August, and November	50	20	9	21	100
March, June, September, and December	50	18	9	23	100

Including the data collected once per year:

January, April, July and October months include up-to-date price information for 68% of the weight of the quarterly CPI.
February, May, August and November months include up-to-date price information for 79% of the weight of the quarterly CPI.
March, June, September and December months include up-to-date information for 77% of the weight of the quarterly CPI.

Publishing this data more frequently as an Indicator provided more timely insights for users about movements in prices at both the aggregate All groups level of the CPI, as well as for the more detailed expenditure class indexes.

The graph below shows that while the monthly Indicator was more volatile than the quarterly CPI – as monthly data will always be – it was also quite effective at achieving the goal of building a picture of the direction of the movement in the quarterly CPI in advance of its release. A step forward from a quarterly read of inflation data.

For instance, taken in isolation, the annual inflation figures for December quarter 2023 (4.1%) and March quarter 2024 (3.6%) suggested that inflation was trending down. The monthly data however showed that inflation had begun to trend sideways or slightly higher, well in advance of the June quarter 2024 (3.8%) data which confirmed the trend. A similar phenomenon was observed between September quarter 2024 and March quarter 2025.

Figure 2: Annual change in monthly CPI Indicator and quarterly CPI series (%)

Image

Description

The chart in figure 2 compares the annual percentage changes in the monthly CPI indicator and quarterly CPI series. Data for this chart is located below under the 'Figure 2 data' heading

Figure 2 data

Figure 2 data
	Monthly CPI indicator	Quarterly CPI
Jan-19	1.2
Feb-19	1.5	1.3
Mar-19	1.6
Apr-19	1.8
May-19	1.5	1.6
Jun-19	1.4
Jul-19	1.6
Aug-19	1.6	1.7
Sep-19	1.7
Oct-19	1.8
Nov-19	1.8	1.8
Dec-19	2.2
Jan-20	2.7
Feb-20	2	2.2
Mar-20	2.1
Apr-20	0.1
May-20	-0.2	-0.3
Jun-20	-0.1
Jul-20	0.8
Aug-20	1.1	0.7
Sep-20	0.4
Oct-20	0.5
Nov-20	1.1	0.9
Dec-20	0.3
Jan-21	0.4
Feb-21	1.1	1.1
Mar-21	0.8
Apr-21	2.5
May-21	3.3	3.8
Jun-21	3.5
Jul-21	2.1
Aug-21	2.5	3
Sep-21	3.1
Oct-21	3
Nov-21	3.2	3.5
Dec-21	3.5
Jan-22	4
Feb-22	4.9	5.1
Mar-22	5.7
Apr-22	5.5
May-22	6.1	6.1
Jun-22	6.8
Jul-22	7.2
Aug-22	7.2	7.3
Sep-22	7.2
Oct-22	7
Nov-22	7.4	7.8
Dec-22	8.4
Jan-23	7.5
Feb-23	6.8	7
Mar-23	6.3
Apr-23	6.7
May-23	5.5	6
Jun-23	5.4
Jul-23	4.9
Aug-23	5.2	5.4
Sep-23	5.6
Oct-23	4.9
Nov-23	4.3	4.1
Dec-23	3.4
Jan-24	3.4
Feb-24	3.4	3.6
Mar-24	3.5
Apr-24	3.6
May-24	4	3.8
Jun-24	3.8
Jul-24	3.5
Aug-24	2.7	2.8
Sep-24	2.1
Oct-24	2.1
Nov-24	2.3	2.4
Dec-24	2.5
Jan-25	2.5
Feb-25	2.4	2.4
Mar-25	2.4
Apr-25	2.4
May-25	2.1	2.1
Jun-25	1.9
Jul-25	2.8
Aug-25	3	3.2
Sep-25	3.5

The complete Monthly CPI

Australia will transition to a complete Monthly CPI on 26 November 2025. The ABS will cease publishing the monthly CPI Indicator with today’s September 2025 publication. Additionally, the complete Monthly CPI will become Australia’s primary measure of headline inflation, replacing the quarterly CPI.

While the monthly CPI Indicator provided valuable insights into Australian inflation it also had limitations due to not all products being priced every month. This had several implications:

Price movements for goods and services measured quarterly were either flat (carried forward) in the months where they weren’t collected or represented three months of price change when they were.
The price change trends for some expenditure classes (for example restaurant meals) presented as ‘steps’ due to the carry forward function when, in reality, the price change across the sector was smoother. The price measurement for other expenditure classes missed short term events such as Black Friday sales.
It was not possible to calculate an unbiased, reliable monthly Trimmed mean measure due to the influence of the carried forward prices.⁸ While the annual Trimmed mean measure included in the publication presented a reasonable view of underlying trends, it was derived by trimming annual rather than monthly movements and so was not as good at accounting for short term changes as a monthly Trimmed mean.
It was still necessary to wait for the inflation picture to build across the months in the quarter.
The publication lacked detail, such as State/Territory indexes, available in the quarterly CPI release.

The ongoing support from Government for the ABS’ modernisation has enabled the ABS to address these issues and to meet the contemporary need for more timely and accurate inflation data. Since April 2024, the ABS has collected data more frequently and replaced the ageing CPI IT system with a secure and efficient cloud environment that can manage the large volumes of data required to produce a complete Monthly CPI.

While the current quarterly CPI has evolved and served Australia well for over 75 years, it is time for the latest evolution in Australia’s inflation data. The forthcoming transition to the complete Monthly CPI will ensure that the ABS can produce high quality statistics about changes in prices which continue to be ‘fraught with importance to every section of the community’.

More information on the complete Monthly CPI can be found on the ABS website via this link Complete monthly measure of the CPI | Australian Bureau of Statistics.

Footnotes

¹ CBCS, Prices, Price Indexes and the Cost of Living in Australia, Labour and Industrial Branch Report No.1, 1912.

² These changes were implemented in the September quarter 1998 publication, following the 13th Series Review of the CPI. For more information see: 6453.0 - Information Paper: Outcomes of The 13th Series Australian Consumer Price Index Review, 1997

³ Source: An update on the annual re-weighting of the Australian CPI and living cost indexes | Australian Bureau of Statistics

⁴ Source: What changes in prices and their collection tell us about Australia | Australian Bureau of Statistics

⁵ Significant examples include: The introduction of scanner data from supermarkets into the CPI (6401.0 - Consumer Price Index, Australia, Sep 2013) and replacing a sample of rents collected from real estate agents with a large administrative dataset which includes over 600,000 rental prices New insights into the rental market | Australian Bureau of Statistics

⁶ Source: Introducing a monthly Consumer Price Index (CPI) indicator for Australia | Australian Bureau of Statistics

⁷ For more information see: Introducing a monthly Consumer Price Index (CPI) indicator for Australia | Australian Bureau of Statistics

⁸ For more information see: Monthly Consumer Price Index Indicator, August 2025 | Australian Bureau of Statistics