So why did a streak of female treasurers continue uninterrupted after Truman appointed Clark?

“Once there’s a woman appointed in a position, it’s easy to assume that position is one that could be filled by a woman,” says Jennifer Lawless, who directs the Women and Politics Institute at American University. “Once an initial ceiling is broken, once an initial piece of progress is made, there is a tendency to continue down that path.”

Such is the power of precedent. Once Clark proved herself capable of excelling at a certain position, future presidents felt less inclined to return to the way things used to be, Lawless said.

Of course, the U.S. treasurer is a much more ceremonial job than the powerful position of treasury secretary—a role that has only ever been held by (white) men, currently by Jack Lew (of meme-worthy signature fame). The current treasurer Rosa Gumataotao Rios, the sixth Latina ever to hold the job, advises top Treasury and finance officials and directly oversees the U.S. Mint and the Bureau of Engraving and Printing. But Rios cannot create policy the way Lew or Yellen can, nor is her job as crucial to the functioning of the administration as theirs is. Ever since a woman was first appointed, the treasurer position has seen long stretches of vacancies—totaling 3,359 days, or nine years.

If this suggests a historical pattern of tokenism, Rios, who previously served as a managing director of investments for a $22 billion investment-management firm, rejects the relevance of any such pattern to her appointment. And in a statement to The Atlantic, the Department of Treasury emphasized the scope of Rios’s job: “While the role of the Treasurer of the United States has evolved over time, today the Treasurer of the United States oversees two major components of the Department of Treasury—the U.S. Mint and the Bureau of Engraving and Printing. This includes managing 4,000 employees and a currency and a coin portfolio with a $4.5 billion budget. The Treasurer is also a senior advisor to the Secretary and Deputy Secretary of Treasury on a wide variety of issues, including community development.”*

Still, according to Alice Eagly, a social psychologist at Northwestern University who studies women and leadership, part of the decision to choose women and minorities for the treasurer position can boil down to “optics.” Eagly notes that it’s easier for presidents to actively engineer diversity with less-scrutinized positions like treasurer, compared with, say, Yellen’s job (for which Yellen wasn’t even the first pick).

But the overall picture becomes more nuanced when you consider that, in addition to their official duties, treasurers also work as ambassadors for economic development in lower-income or under-served communities where the Treasury wants to foster growth. Viewed in this light, “optics” is not a trivial thing, according to Heidi Hartmann, an economist and the founder of the Institute for Women’s Policy Research. Marginalized communities, Hartmann says, tend to be deeply suspicious of the government’s financial institutions. (Also part of the Treasury? The IRS.)