Data for most dimensions of the New Zealand’s gender pay gap data tool is taken from Stats NZ's Household Labour Force Survey, a sample survey of approximately 30,000 respondents which collects income information annually.

Stats NZ calculates New Zealand’s official gender pay gap as the difference between the median hourly earnings of women and men in full- and part-time work.*

All statistical breakdowns are subject to sample error, including the national gender pay gap as reported by Stats NZ. Sample errors increase as further breakdowns are made, for example the gender pay gap between workers aged 15 to 19 is calculated using a very small source group.

In selecting data for this tool, the Ministry for Women has considered long-term trends to ensure any pay gaps reported are real and have continued to manifest over time.

Data is also sourced from the OECD to compare New Zealand’s gender wage gap (a different measure from the gender pay gap) to other OECD countries. This measurement compares the median hourly earnings of women and men in full-time work only. Using this measure, New Zealand’s gender wage gap is consistently one of the lowest in the OECD at 4.2% (as of 2023).

Source data for the field of study report was derived from the Integrated Data Infrastructure (IDI), and provided to the Ministry for Women by the Tertiary Education Commission in 2019. IDI data is not subject to sample error in the same way as survey data, however it does suffer from some attrition where admin data sources cannot be matched. ‘False positives’ may appear when probabilistic matching incorrectly combines some records.

As noted, pay gaps for fields of study have been calculated using the difference in median annual income, and are therefore not directly comparable to pay gaps reported for other dimensions.

For more information on pay differences by qualification and detailed commentary, refer to earlier reports published by the Ministry of Education.

*Note, the Stats NZ gender pay gap calculation methodology differs from the methodology used in the gender pay gap toolkit.