The number of women behind the camera on Hollywood movies jumped to record levels in 2019, with 12 directing top-grossing films including "Frozen II," "Captain Marvel" and "Hustlers," two studies showed on Thursday.

Women made up 10.6% of directors of the top movies last year, more than double the percentage in 2018 and the highest percentage of female directors in the past decade, a study by the Annenberg Inclusion Initiative at the University of Southern California found.

Have you read?

They comprised 20% of all directors, writers, producers, editors and cinematographers on the top 100 grossing films of 2019, up from 16% in 2018, according to a second report by the Center for the study of Women in Television and Film at San Diego State University.

"This is the first time we have seen a shift in hiring practices for female directors in 13 years," said Annenberg study author Stacy L. Smith.

Greta Gerwig's "Little Women" and Olivia Wilde's "Booksmart" also helped propel the record numbers.

The push for more diversity in directing and producing roles has been a major topic in Hollywood for more than a decade, and was given extra impetus by the #MeToo and Time's Up movements, fueled by the sexual harassment scandal that has roiled the entertainment industry.

Yet only one woman - Kathryn Bigelow for "The Hurt Locker" in 2010 - has ever won a best director Oscar, and only four women have been nominated for Hollywood's top awards since 2008, including the Oscars, Golden Globes, Directors Guild Awards, and Critics Choice Awards.

No women were included in the director nominees for the 2020 Golden Globe awards which took place on Sunday, and both Smith and Martha Lauzen in San Diego said more work needed to be done.

"Men continue to outnumber women 4 to 1 in key behind-the-scenes roles. It's odd to talk about reaching historic highs when women remains so far from parity," Lauzen said in a statement.

"We won't know if 2019 was a single good year or the beginning of an upward trend until we see the numbers for 2020 and 2021," Lauzen added.

2020 is already off to a good start with four of the year's most anticipated blockbusters - "Mulan," Wonder Woman 1984," "Black Widow" and "Eternals" - directed by women.

Smith singled out Netflix Inc for praise, saying that 20% of the streaming platform's 2019 directors of U.S. fictional films were women.

"Legacy studios must recognize that the world and the talent pipeline looks vastly different from their hiring practices and act to reflect that reality," she said.