NZ Sources and methods
How published data becomes the figures and claims on this site.
Automated sources are fetched from files or APIs. Manual sources are downloaded into the inbox and validated by the same pipeline. Curated figures are entered from reports with document and page references. Curated rows need a second person in verified_by; unverified rows remain drafts, while self-verification and missing citations block the source.
Validation checks schema, duplicate and unsorted periods, missing values, unexpected jumps, revisions and removed series. Errors block publishing. Warnings need human review; acknowledged warnings retain their reasons. The last valid data remains available when a source is blocked.
We never join different measures. Each retains its definition and unit. Accounting basis changes are recorded on observations, and charts break at those changes and missing periods.
The data pipeline reads source publications and produces versioned CSV and JSON files. Each dataset records its source, licence, retrieval date and a SHA256 fingerprint of the source snapshot. Derived datasets record their formula and input datasets.
The site reads these published files at build time. Factual answers are checked against them during the build. A failed claim stops publication and names the claim that needs review.
Charts break at changes in accounting basis and missing periods. Government term tables use the last available observation before a term begins or ends, and the latest available observation for the current term. Changes during a term do not establish causation.
How NZ election data comparisons work
Luxon's government took office on 27 November 2023. These compare the last reporting period before the 14 October 2023 election with the latest period. Economic shocks, global conditions and earlier decisions also affect the figures.
Quarterly and annual comparisons use the last period ending before 2023-10-14 and the latest published period. Monthly series without seasonal adjustment compare the same calendar month in 2023 as the latest month, ending before the election. Counts such as consents use 12-month totals. These are reporting periods, not estimates for election day. Crime uses the 2023 survey; its survey year includes months after the election. Real GDP per person uses years to March. Real house prices show the percentage change in the OECD index.
Comparisons require the same accounting basis throughout. A missing required comparison period or an incompatible basis stops the claim from publishing. Improvement or deterioration wording appears only where the dataset declares a preferred direction. The largest annual change in a hub summary is the largest absolute percentage change among the key measures listed below it; it does not rank their importance.
Using our sources for NZ statistics
We reformat, combine and calculate from our sources' data. Where we change data (for example adjusting for inflation or dividing by population) we say so on the page. Our sources do not endorse NZ in Numbers or its interpretations.
NZ data sources and licences
Every configured source is listed below. Reported licences still need confirmation; exclusions and attribution are recorded with each source.
- Health New Zealand | Te Whatu Ora: Health targets: 10 years of quarter four results. Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Ministry of Justice: NZ Crime and Victims Survey: how much crime is there. Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Ministry of Business, Innovation and Employment (Tenancy Services): Rental bond data: monthly by region. Creative Commons Attribution 3.0 New Zealand (CC BY 3.0 NZ) (confirmed).
- Ministry of Social Development (MSD): Benefit fact sheets: national benefit tables. Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- OECD: Avoidable mortality. OECD Terms and Conditions (Data), reuse including commercial with citation (reported).
- OECD: GDP per capita (US dollars, PPP). OECD Terms and Conditions (Data), reuse including commercial with citation (reported).
- OECD: Analytical house prices indicators. OECD Terms and Conditions (Data), reuse including commercial with citation (reported).
- OECD: Household gross adjusted disposable income per person (current PPP US dollars). OECD Terms and Conditions (Data), reuse including commercial with citation (reported).
- OECD: Real household gross disposable income per person (OECD dashboard index). OECD Terms and Conditions (Data), reuse including commercial with citation (reported).
- OECD: Income distribution database. OECD Terms and Conditions (Data), reuse including commercial with citation (reported).
- OECD: Health workforce: nurses. OECD Terms and Conditions (Data), reuse including commercial with citation (reported).
- OECD: Purchasing power parities and exchange rates. OECD Terms and Conditions (Data), reuse including commercial with citation (reported).
- OECD: Cancer screening rates. OECD Terms and Conditions (Data), reuse including commercial with citation (reported).
- OECD: Waiting times for elective surgery. OECD Terms and Conditions (Data), reuse including commercial with citation (reported).
- Stats NZ Tatauranga Aotearoa: New dwellings consented per 1,000 residents. Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Stats NZ Tatauranga Aotearoa: Building consents issued (monthly, by region). Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Stats NZ Tatauranga Aotearoa: Adults convicted in court by most serious sentence (calendar years). Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Stats NZ Tatauranga Aotearoa: Adults with finalised charges in court, by outcome (calendar years). Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Stats NZ Tatauranga Aotearoa: Consumers price index (quarterly). Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Stats NZ Tatauranga Aotearoa: Gross domestic product (quarterly release). Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Stats NZ Tatauranga Aotearoa: Household Labour Force Survey. Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Stats NZ Tatauranga Aotearoa: Household income and housing-cost statistics. Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Stats NZ Tatauranga Aotearoa: Labour Cost Index (salary and wage rates). Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Stats NZ Tatauranga Aotearoa: International migration release tables: citizenship and direction. Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Stats NZ Tatauranga Aotearoa: International migration: estimated migration by direction. Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Stats NZ Tatauranga Aotearoa: International migration: arrivals by citizenship and visa. Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Stats NZ Tatauranga Aotearoa: Population estimates: New Zealand estimated resident population at 30 June. Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Stats NZ Tatauranga Aotearoa: Sentenced prisoner population by offence (calendar years). Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Stats NZ Tatauranga Aotearoa: Quarterly Employment Survey. Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- Stats NZ Tatauranga Aotearoa: Selected price indexes (monthly). Creative Commons Attribution 4.0 International (CC BY 4.0) (confirmed).
- The Treasury (New Zealand): Fiscal Time Series – Historical Fiscal Indicators. Creative Commons Attribution 4.0 International (CC BY 4.0) (reported).
- Woolworths Group Limited: Woolworths Group annual reports: New Zealand Food segment (NZ$). No open licence (© Woolworths Group). Individual figures quoted as facts with page citations. (confirmed).
Calculating NZ statistics from source data
These formulas come from the published derived datasets. Their source records identify the input datasets and fingerprints.
- Price changes for food, fuel and rent: Annual change (%) = (index this month ÷ index same month last year − 1) × 100
- Government debt, adjusted for inflation: Real value = nominal value × CPI in the latest year-end quarter ÷ CPI in the quarter of each year-end date
- government spending, tax and debt per person: Per person ($) = Treasury figure ($ million) × 1,000,000 ÷ estimated resident population at 30 June of the same financial year
- Government revenue and spending, adjusted for inflation: Real value = nominal value × average CPI of the latest fiscal year ÷ average CPI of the four quarters in each fiscal year
- Average hourly earnings, adjusted for inflation: Real hourly earnings = nominal hourly earnings × CPI of the latest quarter ÷ CPI of each quarter
- Household incomes compared: NZ and other countries (adjusted for prices): Income (US$ PPP) = median disposable income per equivalised household (local currency) ÷ PPP for actual individual consumption (local currency per US$)
- Household incomes, adjusted for inflation: Real income = nominal income × average CPI of the latest June year ÷ average CPI of the four quarters in each June year
- Inflation rate (annual CPI change): Annual inflation (%) = (CPI this quarter ÷ CPI same quarter last year − 1) × 100
- Migration: arrivals, departures and net (12-month totals): 12-month total = sum of the monthly estimates for the 12 months ending in the month shown
- Pay rates vs prices: are wages keeping up?: Each series: (value this quarter ÷ value same quarter last year − 1) × 100
- Cost of living compared: price levels in NZ and other countries: Price level (US = 100) = PPP for actual individual consumption (local currency per US$) ÷ average market exchange rate (local currency per US$) × 100
- Supermarket profit margin: Woolworths New Zealand EBIT as a share of sales: EBIT margin (%) = EBIT before significant items ÷ total sales × 100 (both NZ$, as reported by Woolworths Group)