Sorry the one I'm thinking of is https://en.wikipedia.org/wiki/Global_Gender_Gap_Report#Criti...

I misremembered World Economic Forum as a part of the UN but it's a separate agency.

But many reports have that bias. For example a report on gender inequality in European Union makes no mention of multiple EU countries conscripting only men.

Look for the Global Gender Gap Report of the World Economic Forum, it uses exactly that metric.