This one picture from the G20 summit perfectly sums up how global politics is an old boys club

Over the past decade and a half, the G20 group of nations has become the main global economic forum supplanting the G8 and effectively setting the tone for the international approach to policy-making. The bigger grouping was supposed to be more diverse than the one it supplanted, including major emerging nations and spanning about 85% of the global population. As its leaders gathered in Hangzhou, China this weekend, however, it was clear that the group still has a long way to go on one metric of diversity: gender.

Of the 36 people on stage at the summit, representing the leaders of the world's most influential nations as well as other institutions, only four were women. This included German Chancellor Angela Merkel – one of the most powerful leaders in the world, man or woman; Park Geun-hye, President of South Korea; Theresa May, the Prime Minister of the United Kingdom and Christine Lagarde, Managing Director of the International Monetary Fund.

Those are all crucial positions to be holding, and yet the sheer disparity in numbers is massive. Put percentage wise, less than 12% of the representatives at the G20 were women. Just in case you weren't sure how incongruous that is, nearly 50% of the world's population is female.

Still, four women on stage actually represents some progress, considering the equivalent platform back in 2008 had only two on stage.

Statistics from the world over tend to drive home this point, that global leadership continues to be terribly skewed in favour of male leaders. Women hold on 21.9% of positions in national parliaments globally, according to the World Economic Forum, and the same is reflected in boardrooms with only 26 female Chief Executive Officers in the list of Fortune 500 nations. As of June 2016, only two countries have 50% or more women in parliament in single or lower houses: Rwanda with 63.8% and Bolivia with 53.1%, according to the United Nations.

And the G20 has a long way to go in making life more equal for its own female constituents. A Thomson Reuters and Rockefeller Group poll of women in the workplace across the G20 countries found that equal pay and work-life balance are still major concerns for women, with surveys also finding that one-third of women are harassed at the work place.

The poll did have some positives though: 43% of women from the millennial generation are confident they will earn the same salary as a man doing the same job, up from 34% of women aged 50 to 64.