There are different methods of measuring the gender pay gap.
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. You can read more about measuring the gender pay gap in Organisational gender pay gaps measurement and analysis guidelines.
We use the same data and methodology as Stats NZ to calculate the gender pay gap figures for different gender and ethnic groups. As a result, our calculations can be directly comparable to the national gender pay gap calculated by Stats NZ back to the first available data from 1998 (where the pay gap was 16.3%).
Hourly earnings (rather than weekly or monthly earnings) are used to remove the effects of women’s higher frequency of part-time work. While women do earn less due to working fewer hours, this is a different issue from the like-for-like pay disparities measured by the gender pay gap.
Median (rather than average or mean) earnings are used to avoid sample error within the survey data of the Household Labour Force Survey.
Other organisations may use alternative calculation methods on gender pay gap figures, such as those using means rather than medians. There is no currently standard measure of pay differences.
For example, Te Kawa Mataaho Public Service Commission calculates a gender pay gap for the public service comparing the average salaries of men and women in full- and part-time work.
The OECD monitors the gender wage gap (a different measure from the gender pay gap) in OECD countries. It 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 9.2%.
Importantly, regardless of how pay gaps are measured, gaps remain between the earnings of women and men.