I realize you're going to get a lot of controversy on something like this but this is a great read. First and foremost, excellent work with the data gathering. Now I want to tinker with TensorFlow.
I think you drew the generally correct conclusion from this:
"But I hope that it will encourage at least some women to think more about their value for an employer and next time will negotiate a better deal for themselves."
My only problem with the conclusion is that statements like this make the assumption that women are not already thinking about their value. My family owns a business that employees almost entirely women with graduate degrees. All very sharp and want to do well in their careers but having diverse interpretations of what doing well actually means to them. Your data is probably better than any I've seen to point that out since it is based on DESIRED salaries.
Some want to advance their careers primarily and while others significantly value flexibility for sake of their families. Men tend to be more singular in focus. We want to advance our careers for sake of ourselves AND our families.
The goals naturally align with a desire to advance in large part to make it easier for our wives to take a pay cut to have more time for the kids. While there are plenty of stay at home dads and role reversals today, the norm is very much the opposite...and it's going to stay that way not because of social acceptance but because of biology...unless of course men start carrying babies for 9 months, going through childbirth, recovering from childbirth, breastfeeding and everything that involves (waking up and night, pumping, freezing milk) and the bond that naturally comes from all of that. Before repeating the process for additional children.
A lot of that stuff is hardwired. I see my wife doing all of that and realize there's only so much I can do to help...but I can try to make more money to make life a little easier.
There are a WHOLE lot of women who decide they want to stop having to work for a while after they've had kids, at least for the early years but then discover that they can't afford too. Between student loans, potentially going overboard on a mortgage from two incomes, etc NOT having a job with the new expense of a child becomes almost unimaginable to handle. There's even a book about it called The Two Income Trap.
All that's to say, don't make the mistake of thinking that people are undervaluing themselves because you don't agree with what they're asking for. You never know what they really want.