There’s a lot less smoking in the movies these days, a new report shows.

Tobacco use on the silver screen peaked in 2005 and has been on the decline since, according to research that looked at the most popular films from 1991 to 2009.

Last year more than half of the 145 top movies released didn’t show any smoking at all. That’s a record for the past two decades.

For films aimed at children or teens, the percentage was even higher: 61 percent. However, 54 percent of the movies rated PG-13 did show tobacco use.

The report “shows that Hollywood is perfectly capable of making movies without as much smoking and people still come see them,” said the study’s lead author, Stan Glantz, director of the Center for Tobacco Control Research and Education at the University of California, San Francisco.

The report was released Thursday in a Centers for Disease Control and Prevention publication.

Glantz and others have been pressuring movie studios for years to cut out smoking in movies marketed to children and teens. Those efforts appear to be paying off, with studios adopting policies on smoking and putting anti-smoking messages on DVDs that depict smoking, he said.

The amount of smoking in PG-13-rated movies is of particular concern, though, because that’s where teens view it most, Glantz said. The more on-screen smoking they see, the more likely they are to pick up the habit themselves, according to the study’s authors.

“There’s a declining trend – which is good to see – but we haven’t made nearly enough progress,” said Ursula Bauer of the CDC.

After years of decline, the smoking rate for high school students has stalled at 1 in 5, which Bauer said could be partly due to the promotion of smoking in movies.

For their study, the researchers tracked tobacco use in the most popular films for nearly two decades. Included were the top 50 films for the years 1991-2001, and films ranked in the weekly top 10 from 2002-2009.

Researchers counted the number of times tobacco use was shown. From a peak of nearly 4,000 in 2005, the number dropped steadily to 1,935 last year.

Since 2007, the Motion Picture Association of America has considered smoking as a factor in its rating system, noting when cigarette use has affected the rating. For example, the PG-13 rating for “Avatar” included “some smoking.”

“This ensures specific information is front and center for parents as they make decisions for their kids,” the association said in a statement Thursday.

Some critics, including Glantz, have pushed for an automatic R rating for films that depict smoking, to serve as an economic incentive to drop tobacco use from their movies to get a less restrictive rating.

The study was partly funded by the American Legacy Foundation, an anti-smoking organization established as part of the settlement between states and the tobacco industry, and the California Tobacco Control Program. Neither group had a role in the research.