Review Committee Endorses CPI Methodology
The 2004 Consumers Price Index Revision Advisory Committee has endorsed the way the CPI is compiled, Government
Statistician Brian Pink said today when releasing the committee's report. The committee also noted that the index in its
current form is well accepted by users.
The committee met in June this year to undertake an independent review of the practices and methods used to compile the
CPI, taking into account the wide-ranging uses of the index. The seven-member committee was chaired by John McDermott,
chief economist of the National Bank. Most of the committee's 20 recommendations call for refinement of, rather than
fundamental changes to, current practices. The recommendations will play a major part in shaping the revised CPI, which
is scheduled for introduction in 2006.
The committee recommended that the CPI should remain an acquisitions-based price index that measures inflation in the
goods and services purchased by resident private households. It concluded that the CPI is well suited for use in the
management of New Zealand monetary policy.
The committee noted that the CPI is also put to other important uses, such as by government, employers and employees
seeking adjustments to benefit payments and wages to maintain living standards in the face of changing costs. As a
result, the committee recommended that Statistics New Zealand develop an additional index or indexes more suited to
measuring changes in the cost of living. Mr Pink supported the potential value of these additional measures, but noted
that current resources do not allow for the development of cost of living indexes. A case for funding will be made when
the additional costs that would be involved have been assessed.
Another recommendation was to review the existing number of 15 regional centres from which prices are collected, in
consultation with users. The review would form part of an integrated sample review of items, regions, field outlets and
brands, undertaken in the lead-up to the 2006 revision.
Currently, fresh fruit and vegetable prices used in the CPI are seasonally adjusted. Other goods and services in the CPI
basket that are known to show seasonality in their prices, such as international airfares, are not seasonally adjusted.
To ensure the CPI better reflects actual short-term movements in prices, the committee recommended that the current
partial seasonal adjustment be removed.
The committee also recommended adopting a standard international classification, which would enable greater
comparability of price change across countries and could potentially harmonise the classification systems used in the
CPI, Household Economic Survey and Household Consumption Expenditure estimates in the National Accounts. This would
enhance integration of the statistics from all three sources.
Mr Pink said he appreciated the major contribution of the committee to the review process and noted that it had provided
him with a very balanced set of recommendations. He said Statistics New Zealand would now develop a programme of work to
implement the recommendations.
Members of the 2004 Consumers Price Index Revision Advisory Committee were: John McDermott (chair), National Bank; Nick
Clark, Business New Zealand; Peter Conway, New Zealand Council of Trade Unions; Peter King, The Family Centre Social
Policy Research Unit; Ralph Lattimore, Nelson Marlborough Institute of Technology; Paul McCarthy, Australian Bureau of
Statistics; and David Scott, Auckland University Department of Statistics.
The Report of the Consumers Price Index Revision Advisory Committee 2004 is available on the Statistics New Zealand
website at www.stats.govt.nz or on request.