Due to the high rates of delinquency against women (including sexual harassment) the authorities of the México City subway decided to apply a security manouevre to keep apart women from the impossible crowds. There isn't a census of the number of users according to gender, but the authorities declare that the female gender represents a bit more of the metropolitan population. So there are two wagons commited to female users at the more crowded stations at traffic peak hours. This sistem has been so succesful, that it has been teached to the subway administrators of other countrys, like Japan for example, 'cause it's an avant-garde operative solution.'