[vilhelm_s]

The usual story (as told in Nathan Ensmenger's "The Computer Boys Take Over") has the change earlier than that. He says in the late 1940s to early 1950s lots of women were hired for "coding" positions, which at the time was seen as a a fairly unskilled, clerical work. In the 1950s, the division between high-level "programmers" and route "coders" disappeared, leaving just programmer-coders who did both, and as a result there was quite a few female programmers. Then in the 1960s the computer industry grew dramatically, but at the same time the image of what a programmer was, and what kind of characteristics made you a good programmer, also shifted a lot, and by the end of the 1960s it had become a very male field.

The personal computer revolution is usually mentioned in connection with a different trend. Throughout the 70s the proportion of female computer science majors was steadily climbing, then somewhere around 1984 this trend broke [1]. It's often said that this has something to do with video games becoming popular toys.

[1] https://www.ultrasaurus.com/2008/11/declining-number-of-wome...