Over the course of researching my book Can’t Even: How the Millennials Became the Burnout Generation, I spent weeks wallowing in the economic history that shaped boomers, days immersed in child-rearing philosophies of the 80s, so much time thinking through how the attitudes of consultants and bankers trickled down to define our understanding of “good work” as “more work.” There were a lot of stats that have clung to me, particularly concerning the overarching idea that we as millennials will be the first generation since World War II to take a step back—not just in terms of health and life expectancy but also wealth accumulation—from our parents.

None of the statistics I encountered were, in truth, that shocking. I knew how much student debt we’ve taken on; I knew how much less time we devote to leisure; I knew just how precarious the millennial experience has become. But one statistic surprised me, and has clung to me ever since I first encountered it: during the last 40 years, women with jobs have spent just as much time parenting as stay-at-home mothers did in the 1970s.