By Eric Kelsey
LOS ANGELES (Reuters) - The number of women working behind the camera in Hollywood's top-grossing films has changed little over the past decade despite a slight uptick last year, an annual study released on Tuesday has found.
The "Celluloid Ceiling" study from San Diego State University's Center for the Study of Women in Television and Film said 7 percent of the top 250 films at the U.S. box office in 2014 were directed by a woman, a 1 percentage point increase from 2013.
"It's not really moving much one way or the other," said study author Martha Lauzen, who added that the number of films directed by women in 2014 has declined to 7 percent from 9 percent since the study began 1998.
Seventeen percent of key off-screen figures - which includes directors, writers, producers, executive producers, editors and cinematographers - were women last year, the study found, also a 1 percentage point rise from 2013 but unchanged from 1998.
"This is clearly an industry-wide problem that requires and industry-wide solution," Lauzen said. "As an industry, film has not taken on this issue of women's chronic underemployment."
The study comes as Hollywood's awards season revs into high gear following Sunday's Golden Globe Awards and the upcoming Academy Awards nominations on Thursday.
Ava DuVernay's historical drama "Selma" is the only early Oscar favorite this year to be directed by a woman, while Angelina Jolie's World War Two biopic "Unbroken" is the only film by a woman to crack the top 100 at the U.S. box office in 2014.
Only one woman, Kathryn Bigelow in 2010 for "The Hurt Locker," has won the best director Oscar in 86 years of Hollywood's top honors.
The study considered 2,822 behind-the-scenes workers and found women were most highly represented as producers at 23 percent and executive producers at 19 percent.
Women comprised 18 percent of editors, 11 percent of writers while cinematographers were the lowest represented job at 5 percent.
Lauzen said one issue facing women is a greater emphasis in Hollywood on ethnic diversity as opposed to gender diversity.
"The sex of the director is incredibly important because the research shows that the sex of the director is related to the percentage of female characters that we seen on screen," Lauzen said.
"This is a very complex industry and a very complex problem," Lauzen added. "There isn't a magic bullet here.
(Editing by Piya Sinha-Roy and Lisa Shumaker)