A new study conducted by researchers from The Ohio State University, USA, looks at the rise in the average age of scientists and engineers in the STEM field's U.S. workforce—a topic that potentially bears both on the country's overall scientific competitiveness and the outlook for younger scientists entering the workforce today. In the study, economists David M. Blau and Bruce A. Weinberg looked in particular at why the workforce is aging rapidly and what that means for science. For instance, they note, "The science and engineering workforce has aged rapidly, both absolutely and relative to the workforce, which is a concern if the large number of older scientists crowds out younger scientists."

The study, published in the Proceedings of the National Academy of Sciences (PNAS) this week, is part of a larger research effort to determine what happens to the creativity and scientists and productivity of scientists as they age. "The conventional wisdom has been that scientists become less creative and innovative as they age," Weinberg said in a press release. However, Weinberg also said that some of his own research suggests otherwise.

Motivating the study—which rested on a combination of data from the U.S. Census Bureau and from a National Science Foundation survey of doctorate recipients conducted between 1993 and 2010—was the rising average of employed scientists in the United States. The average age increased from 45.1 years to 48.6 years between 1993 and 2010, faster than that of the workforce as a whole. And the authors also predict in the paper that the average age will continue to rise, reaching a steady state of 50,9 years in the future, all else being equal.

One reason for concern about an aging scientific workforce is that older, presumably less creative and entrepreneurial scientists might crowd out younger, presumably more innovative and enterprising talent. Weinberg says, however, that those fears have yet to be proven. (Though a press release on the study did admittedly note that the current study can't determine if this is actually happening.) Still, the researchers hope these insights will eventually also help determine if advancing retirement ages are indeed keeping young scientists out of the workforce.

Weinberg says that those fears have yet to be shown as rooted in fact (and, indeed, even Blau and Weinberg's PNAS study doesn't really offer an answer.) Still, the researchers hope the insights in the new paper, coupled with their other work, will eventually also help determine if advancing retirement ages are indeed keeping young scientists out of the workforce.

One reason that the scientific workforce continues to age on the job is that the law in the United States now allows them to do so. A law that had mandated that professors retire at age 70 was repealed in 1994. In the wake of that move, the proportion of scientific workers aged 55 and older ballooned from 18 percent in 1993 to 33 percent in 2010.

This is a significant increase relative to non-scientific fields, for which the proportion of over-55 workers expanded from 15 to 23 percent in the same period. More specifically, the researchers found that a "substantial majority" of the workforce rising in average age is due to the aging of baby boom scientists—of which there is a large cohort in the workforce.

According to the PNAS study, the average age of scientists in nearly all disciplines are on the rise. Even computer and information science—a field historically known for attracting the young and tech-savvy—has, according to a press release, "seen a graying of the workforce." Indeed, almost counterintuitively,  the average age of computer scientists is increasing more rapidly than in other fields.

In addition—somewhat surprisingly, in light of rapid demographic changes—the authors found no correlation or influence on the average age of the scientific workforce with immigration status or gender.

What this rise in average age means for science is yet to be fully understood. The authors  conclude that "The implications of these findings depend on whether and how rapidly scientific productivity declines with age, and whether the life cycle scientific pattern will change in response to the aging scientific workforce." Blau and Weinberg say they'll continue "to investigate the implications of our aging scientific workforce" in their future work.