Female academics at universities throughout New Zealand will be paid $400,000 less than their male counterparts throughout their career, new research reveals.
A University of Canterbury (UC) study has found that a male researcher at a New Zealand university has more than double the odds of being ranked professor or associate professor than a woman with a similar age and research score.
It also found the average male researcher earns more in a lifetime than the average female researcher, with research score and age accounting for only 40-70 per cent of the pay gap, depending on the field.
Even when women and men perform at the same productivity level, women still earn less.
Associate Professor Ann Brower and Associate Professor Alex James analysed data from 6000 academics in New Zealand.
Brower, of UC's School of Earth and Environment and James, of the School of Mathematics and Statistics, found two types of gender disparities in New Zealand universities – a gender pay gap, and a gender performance pay gap.
Their findings support other studies that found gender pay gaps in many industries.
According to figures from Statistics New Zealand the current pay gap of 9.3 per cent has not changed since 2017. It has been trending down since 1998 when the gap was 16.2 per cent.
The new study found the gender performance pay gap varied by field, but averaged about $250,000 over a career.
"We found a man's odds of being ranked – and paid – as professor or associate professor are more than double a woman's with similar recent research score, age, field, and university," Professor Brower said.
"Research score and age explain less than half of the approximately $400,000 lifetime gender pay gap in Aotearoa New Zealand universities... the ivory tower's glass ceiling remains firmly intact."
Even when women were "research stars" they were paid less than men.
The scope of the study allowed the pair to "reject the hypothesis that male dominance amongst the 'superstars' explains the lifetime performance pay gap observed," Professor James said.
"Indeed, women whose research records resemble men's still get paid less than men."
Associate Professor Nicola Gaston of the University of Auckland, and author of the book Why Science is Sexist, said the study added to the growing literature on the gender pay gap.
Gaston said the findings disproved the suggestion that women were paid less because they taught more and completed fewer research papers than men.
"It has been suggested that women may do relatively more teaching than men, and that this is rewarded less when it comes to promotion... however, I do not find it consistent with the findings here," Gaston said.
"That women with equivalent research quality scores are underpromoted by a factor of two compared to men means that something other than research score is holding women back from being promoted."
Gaston said it suggested "a more systemic underlying bias is responsible."
She said a "serious revision of our promotions processes" was required across the New Zealand university system.
The authors of the study also called for immediate change to close the gap.
"We offer some possible explanations for our findings, and show that the gender gap in universities will never disappear in most academic fields if current hiring practices persist," James said.
The paper: 'Research performance and age explain less than half of the gender pay gap in New Zealand universities' was published in the international journal, PLOS ONE today.