In the June quarter 2007, the ABS included two analytical measures of underlying inflation – the Trimmed mean and Weighted median – using seasonally adjusted data in the Consumer Price Index, Australia (cat. no. 6401.0). These measures, which abstract from short-term volatility, are considered useful in identifying underlying trends of price level change and were developed by the Reserve Bank of Australia (RBA).
In December 2010, the ABS completed an extensive review of the Australian Consumer Price Index (CPI) and announced changes to ensure the CPI continues to meet the requirements of the Australian community. The review recommended replacing the 15th series seasonal adjustment methodology used to calculate the underlying trend inflation measures with a methodology using standard ABS practices. For more details about these and other changes to the CPI, please refer to Information Paper: Outcome of the 16th Series Australian Consumer Price Index Review, December 2010 (cat. no. 6469.0).
From the commencement of the 16th series CPI in the September quarter 2011, the ABS will introduce a new 16th series seasonal adjustment methodology to identify and adjust for seasonality. This will replace the 15th series seasonal adjustment methodology.
The non-seasonally adjusted All groups CPI, weighted average of eight capital cities is the official inflation measure. It is not subject to revision. The seasonally adjusted measures will show small revisions from quarter to quarter as the seasonal factors are updated using the latest available data.
Readers wishing to obtain further information about the matters covered in this information paper should contact:
Mr Lewis Conn
Consumer Price Index Section
Australian Bureau of Statistics
PO Box 10
BELCONNEN ACT 2616
Telephone: (02) 6252 7326
Email: <email@example.com >