Why?
That's a serious question.
My hobbies include writing, blacksmithing, cooking, and ceramics.
In writing, around half the people are women.
In blacksmithing perhaps 3% are women.
In cooking probably 90% of the blogs I read and people who take classes are women.
In ceramics it's again 90% female.
I have absolutely no desire to increase the percentage of women blacksmiths...and I have absolutely no desire to decrease the percentage of women pot throwers.
Why should I want to change these?
Why do you want to change the ratio in web development?