What's got four Marks, four Johns, three Simons, two Scotts, two Peters, two Christophers -- but just one woman? New Zealand's leading stock-market index.

Kate McKenzie -- who took the top job at Chorus Ltd. this February and hails from, er, Australia -- is the only woman chief executive officer among the 50 companies on the S&P/NZX 50 index. That's a remarkably poor performance for a country that was the first in the world to give women the vote, and among the first to elect a woman to office.

No English-speaking country does very well on this measure, and chief executives exist at a very thin end of the job distribution curve, so it might be possible to argue that New Zealand's unusually poor performance is just an effect of small sample size.

Female CEOs of S&P/NZX 50 companies


Looking at the far larger population of board members suggests that's not the case. Men have four out of five board posts on half of New Zealand's top 10 companies by market capitalization. Just one of the top 10 company boards in the U.S. and Canada is so male dominated, and none in Australia and the U.K. Overall, women made up just 17 percent of director positions on the NZX in 2016, according to the country's Institute of Directors, versus 27 percent on the U.K.'s FTSE 100, 24.5 percent on Australia's S&P/ASX 200 and 23.3 percent on the U.S.'s S&P 100.

After its third woman Prime Minister Jacinda Ardern assumed office last month, the nation's new minister for women, Julie Anne Genter, has vowed to close the gender pay gap in the public sector within four years. That's an admirable aim -- but unless something starts to change in the private sector too, it's not going to move the needle enough.

Indeed, there's some evidence that New Zealand's egalitarian image on gender issues may have stood in the way of progress, by allowing a degree of undue self-congratulation. The country ranks in the top 10 of the World Economic Forum's global gender gap index and has one of the smallest wage disparities in the OECD's database on the subject. At the same time, the more detailed data produced by New Zealand's Ministry for Women paints a less reassuring picture.

After falling to a low of 9.1 percent in 2012, the difference ticked up as high as 12 percent last year, before declining again to 9.4 percent in the most recent report. A government study led by Professor Gail Pacheco of Auckland University of Technology earlier this year also suggested a discomfiting explanation behind New Zealand's place in international rankings.

New Zealand's pay gap increases sharply with income, from close to zero in the bottom quantiles to more than 20 percent in the top four, the authors found. That may be due in part to the fact that the country has a relatively high minimum wage relative to its median income, they suggested. At low incomes, employers have little scope to discriminate at all in terms of pay, so women do about as well as men. As the opportunities for unequal pay increase, the remuneration divergence does as well.

There's been a "slower sea-change" in New Zealand than in some other countries, says Felicity Caird, manager of the Institute of Directors' governance leadership center, with private sector firms significantly lagging the 45 percent representation now achieved on public sector boards. At the same time, new initiatives should start to improve things, such as the stock exchange's recent requirement that companies report on and set targets for gender diversity.

Given how much of New Zealand's pay-gap problem clusters at the upper echelons, that sort of top-down solution isn't a bad approach to breaking this glass ceiling. By putting pressure on boards to up their game, institutional investors in many countries have helped to improve the gender balance at the highest levels. New Zealand's funds management industry came round to that approach relatively recently, according to Caird, and may have less influence in any case because of its small relative size.

That's no excuse for not trying. As numerous studies have shown, improving the representation of women at senior levels is good for business, improving shareholder returns and risk management as well as making companies more familiar with some of their biggest customers.

The ambitions of New Zealand's government around the public sector are laudable -- but with private companies still falling behind, the country should avoid the temptation to rest on its laurels. After all, the first step to solving a problem is admitting you have one.

This column does not necessarily reflect the opinion of Bloomberg LP and its owners.

David Fickling is a Bloomberg Gadfly columnist covering commodities, as well as industrial and consumer companies. He has been a reporter for Bloomberg News, Dow Jones, the Wall Street Journal, the Financial Times and the Guardian.

To contact the author of this story: David Fickling in Sydney at dfickling@bloomberg.net.

To contact the editor responsible for this story: Katrina Nicholas at knicholas2@bloomberg.net.

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