This page summarises the approach and updates to the development of the monthly consumers price index (CPI).
Monthly CPI background
Stats NZ will publish a monthly CPI from early 2027, following funding announced in Budget 2025. This marks a significant step in providing more timely and relevant inflation data for New Zealanders.
The CPI is a key indicator of economic health. Moving to a monthly release will bring New Zealand in line with other OECD countries and support more informed decision-making about matters that impact businesses and households.
The monthly CPI will be in addition to the quarterly CPI, which we will continue to publish.
How Stats NZ is preparing:
- Modernising technology: A new price indexes environment (PIE) platform is being developed to improve how price data is captured, processed, and analysed.
- Expanding data sources: Stats NZ is looking at innovative ways to collect prices more frequently, without sending out more surveys. This includes expanding the use of scanner data, web scraping, as well as options for more supply agreements and online data acquisition.
- Collaborating with businesses: Stats NZ is working closely with a wide range of industries to ensure timely and accurate data collection.
Regular progress updates will be published to this page.
24 September 2025 update:
Stats NZ is intending to expand the use of three main methods to collect prices data more frequently:
- direct data collections from businesses
- online collections
- other data acquisitions.
Direct data collections from businesses
We will be obtaining data directly from the largest retailers and service providers that consumers use. We aim to provide methods of data delivery that minimise ongoing input from respondents using our data ingestion tools.
We are asking for the following types of data, depending on the business:
- point of sale data (or equivalent for the industry)
- price lists.
'Point of sale' or 'scanner' data enables us to more accurately track the prices paid by consumers over the entire month instead of just at a point in time.
This means that we can:
- account for changes in consumer purchasing behaviour (for example, changing brands or item size)
- account for changes in items on sale (for example, items that change seasonally)
- capture the true impact that specials had on the prices consumers paid.
Collecting prices on a specific day can capture temporary specials, which may cause short-term fluctuations in the price index that do not reflect underlying trends. We will collect this data from larger businesses that may have the largest impact on the CPI.
We will collect price lists from other large businesses where sales patterns are less volatile. While a lot of this data is available online, collecting it directly from businesses provides a more reliable and resilient data delivery mechanism, avoiding the risks associated with manual collection and web scraping.
Online collections
We are looking to expand and enhance our web scraping capabilities. We will utilise web scraping to eliminate burden on smaller businesses. We will use web scraping for an individual business where the impact on the CPI is small and only a few prices are required.
Other data acquisitions
In some cases we will seek to acquire targeted datasets available through third-party data aggregators. We currently do this for selected accommodation, and consumer electronic prices. This method tends to give us more coverage than we could obtain from surveys without engaging with more businesses than necessary.
Enquiries
James Mitchell
[email protected]
04 931 4600
