Economics has always been, and remains, a male-dominated occupation. In Mark Blaug's mid-1980s surveys of great economists before and after Keynes, only three females - Rosa Luxemburg, Irma Adelman and Joan Robinson - appear among his 200 subjects. While only 4 per cent of all Nobel laureates have been female, the gender gap is greatest in the "hard sciences" and economics. Since 1969, of the 61 recipients of the Nobel Prize in Economics, not one has been female. Furthermore, only one of the 30 recipients of the John Bates Clark Medal (the second most prestigious award in economics) has been a woman - namely Susan Athey of Harvard University, who received her award in April 2007.
This gender gap also remains significant in academic economics departments and among undergraduate and postgraduate economics students.
Concern in the US relating to the gender imbalance and the status of women working in academic economics led to the formation in 1971 of the Committee on the Status of Women in the Economics Profession. In the UK, the role of this committee is mirrored by the women's committee of the Royal Economic Society, whose primary objective is to increase the number of female economists at all levels in UK academia and business.
But has there been any significant change in the gender balance within US and UK academia since the early 1970s? The representation of female economists at all levels within US academia increased significantly between 1971 and the 1990s, but in 2006 only 21 per cent of tenured assistant professors, 24 per cent of associate professors and 8 per cent of full professors were women. Data from the American Economic Association on the total number of bachelors, masters and PhD economics degrees awarded indicates that for a total of 217 institutions in 2004-05, the percentage of females in each category was 34, 40 and 30 respectively. While from 1991 to 2006 the proportion of females among economics graduates increased from 29 per cent to 31 per cent, this modest expansion must be viewed against a backdrop in which the proportion of females in the total undergraduate population increased from 54 per cent to 59 per cent.
A recent Royal Economic Society survey, conducted by Andreas Georgiadis and Alan Manning, found that in the UK, 9 per cent of professors, 21 per cent of readers, 19 per cent of senior lecturers and 24 per cent of permanent lecturers were female. In total, including full-time, part-time and research appointments, only 20 per cent of academic staff in economics were women. Thus while the position of female academic economists has improved over the past 30 years, women "remain a small minority among academic economists, and are heavily under-represented among the more senior grades", according to the survey.
One problem facing all female academics who plan to have children relates to the potential conflict, especially in the US, between the tenure clock and the biological clock. For example, the average female PhD recipient in the US is 34, and as Harvard's first tenured female economics professor, Claudia Goldin, observes: "The most important question facing women graduating today is whether they can find a job where it is possible to combine family and career." This remains a significant problem in any occupation involving a total commitment in terms of long working hours. But why is this acting as a more significant constraint in economics than in other academic disciplines?
Some explanations emphasise demand-side factors, such as discrimination and nepotism in appointments and promotions. However, in countries where anti-gender discrimination legislation has been enacted and regularly enforced, we may have to look elsewhere for reasons.
Other explanations focus on supply-side factors, such as a possible lack of interest among females in the content of economics and its increasingly technical and mathematical nature, a lack of female role models and mentors within academia and a difference in individual gender preferences for fields of study.
But perhaps the main reason is simply that for too long economics has been viewed as a "male subject" that is unattractive to most women. This is a false image and it is about time that economists - as one - did a better job at showing how economics can contribute to a better understanding of almost all the major issues that confront the world economy in the 21st century.
Brian Snowdon is professor of economics and international business, Newcastle Business School at Northumbria University.