Harvard University's Claudia Goldin has won the 2023 Nobel Prize in Economics for her research on women in the labor market. She studies the changing role of working women through the centuries, and the causes of the persistent pay gap between men and women.

The award — formally known as The Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel — comes with a prize of 11 million kronor, or about $1 million. Goldin is the third woman to receive the prize.

"Claudia Goldin's discoveries have vast society implications," said Randi Hjalmarsson, a member of the Nobel committee. "She has shown us that the nature of this problem or the source of these underlying gender gaps changes throughout history and with the course of development."

Goldin's research showed that women's role in the job market has not moved in a straight line, but has waxed and waned in line with social norms and women's own ideas about their prospects in the workplace and the home. Some of these ideas are shaped early in life and are slow to change.

"She can explain why the gender gap suddenly started to close in the 1980s and the surprising role of the birth control pill and changing expectation," Hjalmarsson said. "And she can explain why the earnings gap has stopped closing today and the role of parenthood."

Tracing the history of women in the workplace was easier said than done. The Nobel committee said Goldin often had to contend with spotty records.

The earnings disparity between men and women narrowed as more women went to work. But it didn’t go away.

Goldin compiled two centuries of data on the gender pay disparity. She found that the earnings gap narrowed during the first half of the 19th century and then from roughly 1890 to 1930 as companies began to need many more administrative and clerical workers.

But progress in reducing the pay gap stalled from about 1930 to 1980 even though more women were working and attending college.

Goldin identified the key culprit: Parenthood. Once a woman has a child, her pay tends to drop and subsequently doesn't grow as fast as it does for men, even among women and men with similar educational and professional backgrounds.

Modern pay systems tend to reward employees with long, uninterrupted careers. And companies often demand that employees be available at all times and flexible about working late and on weekends. That can be difficult for women who typically bear more childcare responsibilities than men do.