Google's Ngram Viewer uses Google Books' massive collection of 5 million texts published over the last 200 years to track trends. Last month we saw "love" has decreased in popularity while "sex" has risen, and now we're using it to look at gender roles.
Well, actually Chris Harrison, a human-computer interaction PhD student at Carnegie Mellon, is using it; we're just reaping the reward. To examine how men and women have been portrayed in writing, he did some Ngram tricks, which I can't begin to comprehend, to find the 120 most common words following "he" and "she." Then he ordered them in decreasing frequency on the above chart to illuminate basically everything we already know about stereotypical gender roles. Men are the doers; women are the givers.
"He argues" and "he can" while "she loves" and "she learns." This may tell us nothing new about the social milieu of the last two centuries, but it does highlight how gender roles were reinforced long before rom-coms and Disney. Because actions may speak louder than words, but words, well, they last longer.