Obviously, there is an easy solution for this problem, eliminate the gap in these sectors: Nat. resources, agriculture, Manufacturing, utilities, Transport and compare similar positions, i.e. a rig worker with  a rig worker not an office clerk. Make digging in a dirt a glamorous job and more females will follow, because nothing is better for your skin then working outside in a freezing cold. Leave it to immigrants to bear children while you persuading equality working longer hours. Later when dying at the old age you will regret that din't work more.