O Women entered the workforce in much larger numbers than they had in the past.
Explanation:
During the world war in 1940s, Large portion of women started to enter the workforce to replace the men who were drafted into the war. During this time They erased the initial perception that women couldn't do as good as a job as their men counterpart.
When the war ended, many of the companies still keep their female workers due to their productivity. The number of female workers keep increasing ever since that time.
During 1950s, number around 33% of workers in united states were Women. (Before the war it's only around 10%)
