A report to be released Wednesday by the Media, Diversity and Social Change Initiative at the University of Southern California's Annenberg School for Communication and Journalism finds little evidence of Hollywood improving in the diversity of its movie characters or directors. The study has been a nearly annual effort going back to 2007, each year studying the demographics of the 100 most popular films at the North American box office. Here are some of the study's key findings from 2015's top films:

GENDER

— Out of 4,370 speaking or named characters in 2015's top films, 68.6 percent were male, 31.4 percent were female.

— From the 2015 films, 32 percent featured a female lead or co-lead, an 11 percent increase from 2014.

— Females were far more likely than males to be shown in sexually revealing clothing or nude: 30.2 percent to 7.7 percent.

— Of the 107 directors for 2015's top films, 81 percent were male and 19 percent were female.

RACE

— In 2015's top films, 73.7 percent of speaking or named characters were white, 12.2 percent were black, 5.3 percent were Latino and 3.9 percent were Asian.

— Those rates are similar to those from 2007.

— There was not one Asian lead or co-lead in 2015's top movies.

— Four of the 107 directors in the 2015 films studied were black or African American. Six were Asian or Asian American.

LGBT

— Out of the 4,370 speaking or named characters in 2015's top films, 32 were identified as lesbian, gay, bisexual or transgender.

— There was not one LGBT identified lead or co-lead character in 2015's top films.

CHARACTERS WITH DISABILITIES

— Out of the 4,370 speaking or named characters in 2015's top films, 2.4 percent were shown with a disability.