Its not as simple as saying it should be 50:50 though is it.
However unfair it is many women make time for children and so are out of the workplace, this means their experience drops and in some cases for quite a few years.
Having said that I think there is still a way to go but we will get there. The important thing is that it is done on merit not tick boxing otherwise it demeans the achievements of those that have worked hard and are good at their job.