2019-2020 Big Physics Question

Women have made tremendous contributions to the advancement of physics. Consider the work of Marie Curie, Maria Goppert-Mayer, Chien-Shiung Wu, Jocelyn Bell Burnell, Emmy Noether, and Vera Rubin. Yet as of 2019, only 20% of physics PhD's in the USA are held by women (see figure below).

The question: How can we achieve an equal number of women as men pursuing physics degrees by 2040?

Figure take from AIP Statistical Research