This is a guest post by Nicole Hallberg, one of the writers behind Vox’s viral “Sexism In The Workplace” experiment. In that piece, she documented what it was like to swap names with a male counterpart for email correspondence, and wrote about the difference in treatment they received based on perceived gender. 

If a person in your organization was assigned and completed more work than anyone else, would you promote them? According to data collected by Hive, 54.9% of tasks are assigned to women, compared to 45.1% assigned to men. Both genders completed tasks assigned to them at a similar rate of 66%, meaning that women contributed 10% more productivity to their organizations overall. And yet, women make up only a tiny fraction of company leadership, and the fraction gets tinier (and whiter) the higher up the ladder you climb. So, where are all of these super-productive women leaders? Why aren’t there more women in the C-Suite? Check the break room—they might be busy doing the work that no one else wants to do.

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I eat, sleep, and breathe issues of gender and equality as a writer, so when Hive approached me with a report of gender workplace data collected by their platform, I dove into it. Hive was able to collect anonymized data based on the actual work habits of 3,000 men and women—not self-reported info. Several statistics jumped out at me, but I kept coming back to the fact that women contribute more overall productivity, yet are valued less. Why is that?

Busywork vs. Promotable Work

Not all work is created equal. The brunt of office busywork and housekeeping tasks tends to fall disproportionately to women who are “volun-told” to do things like empty the office dishwasher, fetch coffee, order consumables, arrange for lunch delivery, take meeting notes, and organize office parties. I’ve interviewed several women in my line of work as a blogger who expressed frustration at these sexist expectations—that even the women in management positions were asked to do tasks that would normally be expected of administrative assistants, while lower-ranking men were not. It seems that we still can’t wrap our heads around asking a man to do anything in the office kitchen, even if they are willing to pitch in (which, they’re not—at least not as often as women, according to an American Economic Review study that shows that women are 48% more likely to volunteer and 26% more likely to agree to do thankless office tasks when asked.)

Pitching in for the greater good and comfort of the office environment isn’t a bad thing, but it becomes a bad thing when women’s careers stagnate under the added burden of non-promotable tasks. No manager has ever uttered the words “I’m really impressed with how you automatically take the meeting minutes every week and have been the only one keeping the office plants alive, so I’m going to recommend you for the corner office.” A boss might appreciate those kinds of contributions, but they do not value them. Or, to take a more cynical view, they might not notice that anyone is doing it at all.

How Unrecognized Emotional Labor Limits Women’s Ability to Achieve

We live with a system that chronically undervalues the contributions of women by refusing to recognize our labor as work, even when these tasks are critical to the function of our workplaces (and homes). Part of the problem is that some of the tasks that take up the most space in our brains and cause the most emotional fatigue during the day aren’t strictly “tasks.” Who in the office remembers birthdays and makes sure everyone signs the card? Who is making sure that there is allergy-friendly food available at the company picnic? Who goes out of their way to ask about a coworker’s sick family member? Tasks like these are known as emotional labor, and it takes up an incredible amount of real estate in the minds of women who are not rewarded for doing them, but are punished for neglecting them.

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A 2005 study found that men were given higher performance reviews when they pitched in on office housework, but didn’t suffer any loss when they didn’t. On the flipside, they found that women’s performance reviews suffered when they neglected to pitch in, but stayed the same when they did. How do you get ahead with all these extra chores crowding out your agenda, with no recognition for any of it?

So, What Do We Do About It?

Despite women’s recorded ability to get more done in the same amount of time as men, (likely due to overcompensation in response to fewer opportunities and lack of recognition) they’re promoted much slower than their male peers and they don’t tend to make it all the way to executive roles. The issue — a massive lack of women in the C-Suite — can’t be solved by advising women to refuse grunt work, because that carries the aforementioned social and professional penalty for women that men have never had to think about. And if everyone refuses to do the grunt work, you could end up with a toxic work environment that grinds productivity to a halt.

The solution here is not for women to figure out how to opt out of sexist expectations and repercussions while also making reservations for the team bonding activity and working on landing the new key account. The solution, rather, is for more men to wash out their own coffee mugs, volunteer to bring in the cupcakes, and be vocal to their superiors about their female peers’ valuable contributions to the team. If you’re already doing those things, bravo—now go encourage your coworkers to do it too so we can keep making progressive change towards a more equal workplace.