President Trump delivers his State of the Union speech Jan. 30 before members of Congress, many of whom won’t be there next year. (Photo illustration by Melina Mara/The Washington Post)

House Speaker Paul D. Ryan’s semi-surprise announcement on Wednesday that he would not seek reelection was unusual in the sense that no speaker of the House has made a move like that since … well, since the guy before Ryan. But before that, being speaker was the sort of thing that people fought for their entire careers. So it’s weird, in that context, that Ryan (R-Wis.) would simply walk away.

But not weird in two other senses. The first is that being a Republican House speaker at this moment is almost certainly nightmarish for a variety of reasons, the sort of horror-show job that would drive two people away in less than three years. The other reason it’s not weird is that more than 16 percent of Republicans sitting in the House have already announced that they don’t plan to return.

If you were wondering, that’s a lot.

There are a lot of Democrats who’ve said they don’t plan to seek reelection, too, the second most at this point in an election cycle since at least 2006, according to data compiled by Daily Kos. Only in 2012 were there more Democratic retirements.

The Republican picture is dramatically different. By last fall, the number of retirements was easily outpacing past election cycles. In 2018, there have been 50 percent more announced retirements than there were in 2008, the previous high at this point in the election cycle.

As a result of that surge in Republican retirements, the overall number of retirements so far this year is also higher than it has been before any election in more than a decade.

There have been more retirements before Election Day this year than there were at Election Day in any election from 2006 to 2016. The average last retirement over that period was 87 days before the election — meaning that the total this year can be expected to keep rising until about mid-August.

This is generally accepted as not-great news for the Republicans, given that incumbents have an advantage in congressional races. But there is not really much correlation between the net difference between Democratic and Republican retirements and the shift in seats won in the House on Election Day. You’d expect the bars on the graph below to go in opposite directions — the party with more retirements winning fewer seats — but that has not really been how it works.

In fact, the difference between the number of retirements between the two parties isn’t itself exceptional. At this point in 2008, the difference between the number of announced Republican retirements and Democratic retirements was about the same.

In 2008, the Democrats gained seats — but fewer than they had two years prior. Lots of other factors come into play.

For example, sometimes a party may be on its heels but has a leader who’s a prodigious fundraiser and helps the party power through. The Republicans have that — until January, anyway.