Back then, movies were rated G, M, R, or X. Of course, the M later became the PG we're used to seeing today. Over the past 45 years, the ratings system also came to include the PG-13 rating in 1984.

Since 2009, the level of gun violence in PG-13 films has been as high as or higher than in R-rated films and has exceeded that level since 2012, the analysis shows. For parents, these findings are ...

Because they play to a smaller audience, R-rated movies usually don't earn anywhere near as much as PG-13 films do. Last year, 187 R-rated films brought in $2.9 billion at theaters.

That's an average of $16.8 million per R-rated film. Compare that with the 119 PG-13 rated movies that brought in $5.6 billion in 2012, for an average of $47.3 million per film.

The prevalence of gun violence in top PG-13 movies has more than tripled since the rating was introduced in the mid-1980s, and last year it eclipsed even the amount in R-rated movies, according to ...

A new study has found that the level of gun violence in mainstream U.S. pics has more than doubled since 1950, with the level of gunplay in PG-13 movies now outpacing that of R-rated pics.