David Leonhardt of The New York Times examines a study that came out last year, showing a growing happiness gap between men and women since the 1960s.  In the 1970s, women reported being slightly happier than men, however, since then, women's happiness has been on the decline.  Men now report being happier than women.  Why?

What has changed — and what seems to be the most likely explanation for the happiness trends — is that women now have a much longer to-do list than they once did (including helping their aging parents). They can’t possibly get it all done, and many end up feeling as if they are somehow falling short ...

Betsey Stevenson, an economist at the University of Pennsylvania, explains it this way, that women were happier three decades ago becauuse they had "narrower ambitions," and compared themselves only to other women.  Stevenson recollects a conversation with a student:

Her mother’s goals in life, the student said, were to have a beautiful garden, a well-kept house and well-adjusted children who did well in school. "I sort of want all those things, too," the student said, as Ms. Stevenson recalled, "but I also want to have a great career and have an impact on the broader world."