On Wednesday afternoon, Representative Mike Conaway, Republican of Texas, announced that he would not run for re-election next year. At a news conference in Midland, Mr. Conaway expressed distress at the partisan dysfunction in Congress, nodded to the term limits that his party places on committee leadership positions and said he’d been pondering retirement for a year or so. He said he wanted to leave on his “own terms.”

After eight terms in the House, the 71-year-old Mr. Conaway is entitled to a new adventure. But as the fifth congressional Republican to issue a retirement announcement in the past two weeks — and the eighth this year — his decision is being received as more than a personal choice. It’s being seen as evidence that Republican lawmakers are not feeling upbeat about retaking control of the House in 2020. Some party strategists have said they expect the trend to accelerate, with another round of announcements after members return from the August recess.

While it’s too soon for House Republicans to panic, some anxiety does seem to be in order.

Besides Mr. Conaway, Utah’s Rob Bishop confirmed his retirement on Monday , and Alabama’s Martha Roby announced hers on Friday, one day after the announcement by Pete Olson of Texas, which came one day after the announcement by Paul Mitchell of Michigan. Indiana’s Susan Brooks announced her retirement in June. Georgia’s Rob Woodall did the same in February. And in January, just two weeks after being sworn in, Pennsylvania’s Tom Marino resigned. (He was replaced in a special election in May by another Republican.)

Adding to the churn, Alabama’s Bradley Byrne and Montana’s Greg Gianforte are running for other offices, while Texas’ John Ratcliffe has been nominated as the next director of national intelligence. Wyoming’s Liz Cheney is mulling a bid to replace retiring Senator Mike Enzi. And let’s not forget Justin Amash of Michigan, who switched from Republican to Independent in disgust on July 4.