Claudia Goldin, an economist at Harvard University, sees many factors behind the shift.

WSJ: Women Set New Goals for Careers and Lives

Some economists, such as Claudia Goldin and Lawrence Katz, trace the growing pay gap to increasing demand for skilled workers.

ECONOMIST: Economics focus

Harvard economist Claudia Goldin recalls that, unlike her own cohort of early baby boomers, these younger women didn't plan to postpone family life while pursuing career goals.

WSJ: Virginia Postrel on the Mommy Track | Commerce & Culture

In their 2008 book, The Race Between Education and Technology, Harvard economists Claudia Goldin and Laurence Katz argue that technological advancement was a major spur to educational attainment for the U.S., at least until the 1970s, and that this symbiotic relationship laid the grounds for almost a century of American prosperity and relative economic equality.

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