It’s not your imagination. There’s a good chance that the 1989 Patrick Swayze starrer “Road House” is playing on TV every time you surf the dial. So are “Ghostbusters” and “Friday” and “50 First Dates” and “Jumanji” and “Legally Blonde” and “A Few Good Men” and a host of other evergreen titles that defy gravity and deliver steady ratings.

Big box office hits from the 1980s, ’90s and early 2000s are among the most reliable performers for ad-supported cable. Despite the wide availability of movies in commercial-free, uncut and on-demand formats, the umpteenth airing of “Independence Day” on AMC or TNT is likely to draw a reliable 300,000-500,000 viewers no matter the daypart. Industry veterans say movies act as “flypaper” that grab audiences — precisely because they are so familiar. A fan of “Pretty Woman” or “The Shawshank Redemption” can come in at any point and know every line of the script.

Typically, viewers stick around for about 17 to 20 minutes of a movie airing in a two-hour time slot, which is enough to monetize them through at least one commercial break. “It’s the opposite of appointment viewing — it’s collision viewing,” says Ken Werner, former president of Warner Bros. Domestic TV Distribution, about movies airing on ad-supported cable. “You’re giving the audience something that they want even though they’re not searching for it. You’re just entertaining them for a moment in time.”

The standards of movie licensing have changed markedly in recent years, and that’s one reason why prominent titles can play across multiple networks within a few months. In the past, cablers would commit to licensing big packages of movies from the major studios for terms of four years or more. Today, Warner Bros. and other studios often license a smaller collections of titles for a matter of months. That allows movie owners to make the most of their titles while cablers don’t have to pay as much and don’t have to hold that inventory for so long.

Basic cablers have used movie airings as the original “recommended for you” algorithm for years. Crowd-pleasing titles are often tapped as the lead-in for original series launches. On March 12, 2002, an airing of 1991’s “Terminator 2: Judgment Day” was the launchpad for “The Shield,” the police drama that put FX on the map as a player with original series.

” ‘Terminator 2’ taught me everything I needed to know about the incredible power of beloved movies, and how you can match demographic appeal to what we’re trying to launch to make sure the audience sees the show,” says Chuck Saftler, president and COO of FX Networks and the group’s longtime head of scheduling.

These days, the fact that most movie viewing on cable is done live means that commercials and promo spots have more punch.

“With movies, it’s like flypaper. You can get people to join you at any time through the movie and they tend to stay longer than they think they’re going to,” Saftler says. “When you have a two-hour strip of flypaper where viewers just land and stick, it’s a great way to program a large chunk of time and to promote other shows. Because people are watching live and not DVR-ing, they’re actually seeing the promos.”

Here’s a look at 100 of the most widely played movies on basic cable for the 2019-20 season to date (Sept. 23-July 3), listed by genre and the number of airings per channel.