There is such a thing as a 'wife bonus'. In other news, it is 2015

Dr Wednesday Martin is a writer and social researcher who has been studying the upper echelons of New York society for six years.

During that time she discovered wife 'bonuses' - where stay-at-home spouses are given extra cash for performing their wifely duties well "in the same way their husbands were rewarded at investment banks".

As Dr Martin explains in a piece for the New York Times, the terms are usually pre-agreed and the cash gives women a degree of freedom. "These bonuses were a ticket to a modicum of financial independence and participation in a social sphere where you don’t just go to lunch, you buy a $10,000 table at the benefit luncheon a friend is hosting," she writes. "Women who didn’t get them joked about possible sexual performance metrics."

As for what this all means?

It made sense only in the context of the rigidly gendered social lives of the women I studied. The worldwide ethnographic data is clear: The more stratified and hierarchical the society, and the more sex segregated, the lower the status of women.

Wednesday Martin's Primates of Park Avenue is out in June.

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