House Speaker Paul D. Ryan has announced that he will retire from Congress when his term expires in January. This comes as little surprise: The Republican Party’s majority in the House is in serious jeopardy, rumors have circulated for months that Ryan would leave and he was reluctant to be speaker in the first place.

What makes his departure unusual is that he will have completed a full term as speaker in the current Congress. Although most representatives and senators end their careers that way, speakers don’t. In fact, Ryan would be the first to do so in more than three decades.

Speaker used to be a pretty secure job. Turnover was low, party majorities were electorally safe, and those who served as speaker were mostly scandal-free and strongly supported by their fellow partisans. In fact, between 1933 and 1986, every speaker of the House (with one exception — Joe Martin of Massachusetts) ended his speakership by either dying or retiring at the end of a term.

In 1989, Speaker Jim Wright of Texas broke that streak. Accused of ethical improprieties amid eroding support within the Democratic caucus, he resigned in the middle of his second term as speaker.

That’s when the speakership became a far less secure post. Wright’s five successors either lost reelection, as happened with Tom Foley (D-Wash.) in 1994; resigned midterm, as happened with Newt Gingrich (R-Ga.) in 1998 and John A. Boehner (R-Ohio) in 2015; or lost the speakership when their party was booted from the majority, as happened with J. Dennis Hastert (R-Ill.) in 2006 and Nancy Pelosi (D-Calif.) in 2010.

What does this mean for whoever fills Ryan’s shoes? Ryan may prove to be an exception to this tumultuous pattern for speaker. The factors contributing to instability in the office — including strong competition for control of Congress and heightened divisions within congressional parties — remain in place. After all, had Ryan not opted to retire, he might have suffered the same fate as Hastert and Pelosi, losing the speakership because his party lost control of the House.

But there is the possibility, however remote, that we are entering a new era in which speakers are more safely ensconced in their post. The last time the speakership was this unstable was during the late 19th century, for a period that lasted about the same length of time as the one we are in today (34 years, from 1869 to 1903). Perhaps the speakership is returning to a state in which it is a little more secure for those lucky (or unlucky) enough to serve.

Editors’ note: An earlier version of this post incorrectly stated Rep. Foley’s home state. 

Matthew Green is a professor of politics at Catholic University, author “The Speaker of the House: A Study of Leadership” (Yale University Press, 2010) and co-author with Douglas Harris of the forthcoming “Choosing the Leader: Leadership Elections in the U.S. House of Representatives” (Yale University Press, 2019).