On the flipside, with regard to pedestrians going over the ANZAC Bridge, my unscientific count puts the ratio at 10 women for every man. I have a theory about this, and it relates to sweaty hair. Men do not generally need to blow dry their hair after a shower. At least not manly men. Most women need to, as well as apply makeup etc. I have never worked with a bloke that wore makeup to work. They might wear makeup after hours, but not in the office. I think women simply prefer to go through that rigmarole in the privacy of their home, as opposed to a common shower area at the office.
If you ride, you have to wear a helmet, and if you ride any distance, your hair will be a sweaty mess. A shampoo after a ride is a must for me. If you choose to walk, you won't get as sweaty, so the whole shower/shampoo/blow dry/makeup thing is not an issue.
Would more women cycle if compulsory helmet laws were revoked?