Books do more than make money
Waldfogel’s paper used revenue as a proxy, along with a few other measures, to discover the “welfare” effect of books: how much they benefited those who read them. He concluded, overall, that the influx of female authors increased the welfare of a diverse set of readers, by offering them things they wouldn’t have been able to get had the female influx not occurred. These books might, for example, have offered narratives and perspectives that would otherwise have gone unwritten. Revenue overall rose by between a tenth and a fifth with the influx of female authors, he found.