Historically, families have always had at least two “incomes.” Even people who buy into a strict division of labour between the sexes concede that all sexes brought food to the table, from picking berries to doing farm chores. This is quite stable against adversity; if one person cannot provide for the family, they can try to subsist on another person’s contribution. Arbitrary restrictions on what each sex can do artificially limit that capacity, and endanger survival.
On rare occasions, though, a single provider has been enough to feed an entire family. Artificial restrictions aren’t a factor anymore, and don’t face the opposition they would in a two+ income society. But of course, no culture has ever fit on that extreme, so you wind up with a mixture of both. Nor has any culture been free of economic swings down to the individual level.
This suggests a theory: during economic downswings, societies are pushed towards feminist attitudes, as sexist attitudes squander human resources. During upswings, there is no strong draw either way, but as it’s tougher to correct justice than perpetuate it societies tend to gradually drift towards anti-feminist attitudes. I dub this “.”
Early drafts of that paper included two anecdotes to support this. Iceland, for instance, has been sympathetic to feminism for some time. In 1975, a radical woman’s movement called the Red Stockings suggested all women should go on strike. This came to pass on October 24th, when 90% of Iceland’s women refused to work or look after the children. Yet by 2009, Iceland had a greater gender pay gap than all of Europe, one that persists to this day. Why? Well, Iceland was profiting greatly from the housing bubble in the USA, thanks to deregulation and aggressive investment in foreign countries, which led to a huge economic boom in a small country. As banking was predominantly a male profession there, this inflated the gender pay gap.
Iceland suffered a significant economic crash in 2009, a 10% loss in GDP between 2008 and 2010. In response, during the 2009 election they voted in Jóhanna Sigurðardóttir as Prime Minister, the first woman to hold that position in Iceland and the first world leader to be openly lesbian. Her government implemented a vast number of reforms, most notably the criminalization of the purchase of sex and the shutdown of all strip bars in 2009; gender quotas were implemented in 2010, as well as a bill allowing single women to receive donor sperm.
Japan saw an incredible economic boom after WWII, thanks in part to shrewd investment in infrastructure and foreign economies, plus a practice of tight industry-government and industry-industry relations that reduced bureaucracy and waste due to competition.  With only one income necessary to sustain a family, and every person promised a job for life, their culture drifted towards heavy sexism. So what happened after that bubble burst?
Japan has suffered from a decade-long recession, and seen sluggish growth in comparison to other developed nations. In 2006, Maki Fukasawa wrote an article on what she dubbed “soushoku danshi” or “grass-eating boys,” who rejected the strict gender roles that their fathers had embraced and were exploring behaviors previously held to be feminine. Roughly 60% of men under 23 now fall into this category, and 42% of those between 23 and 34. The last decade has also seen the rise of “nikushoku onna,” or “carnivorous women,” who also reject traditional roles by taking the initiative in relationships and pursuing men more aggressively.
Digging up supportive anecdotes is pretty easy, though. In my paper, I look at two decades worth of global economic data in search of a similar effect. Child care is almost universally undervalued, but in a contradictory way: parents looking after their children receive no income and few benefits for it, yet third parties looking after children do earn an income.
This means that during an economic downturn, the shift from single to multiple income would cause a “boost” in overall GDP and smooth out small economic bumps. It isn’t an actual boost, mind, it’s just that an undervalued task is being assigned more value. A 100% feminist society would see no cushion, because child care would not be undervalued, and a 100% sexist society would see no cushion, because gender norms would prevent the necessary economic mobility. Interestingly, this also provides a secondary way to measure the gender gap: if women are truly undervalued compared to men, then an influx of women would have less of a “boost” than an influx of men. By comparing the size of each effect, we can measure the gender income gap on a global level.
And I found… pretty much what you’d expect. The cushion effect exists, and it’s greater for an influx of men than it is for an influx of women..
 Rudolfsdottir, Annadis. “
 Eurostat, “ .”
 J.E. Johnson, “ .” The Nation, February 21st 2011.
 Jesse Colombo, “ “. June 4th, 2012.
 A. Harney, “ .” Slate, June 15th, 2009.