This is the most diverse year in Oscars history, and thanks to a new UCLA study, we now know why.

According to UCLA's bi-annual Hollywood Diversity Report, which for 2021 is subtitled "Pandemic In Progress," Hollywood made enormous strides last year with regard to inclusion for women and people of color both in front of, and behind, the camera.

The report usually covers only theatrical releases, but (like the Academy Awards) this year it also includes streaming to account for the way audiences saw movies in 2020.

Among its findings: women and people of color gained ground in each job category it tracks (lead actors, total cast, writers and directors).

In the top 185 films released, the report finds that people of color made up 39.7% of leading roles, a marked improvement from 2014, when UCLA launched the study, when people of color represented just 10.5%. Women had 47.8% of film leads, as opposed to 25.6% in 2011.

And that diversity appears to be what audiences are looking for. The report found that on average, films with between 41-50% minority casts fared best at the box office, while films with less than 11% minorities fared worst.

The report acknowledges that all of these numbers were affected by the fact that film studios held off on releasing many of their big-budget attractions in cinemas, and that streaming services picked up many mid-range films.

"Our report finds that women directors and directors of color have overwhelmingly diverse productions," said Ana-Christina Ramon, the report's co-author and the director of research and civic engagement for UCLA's division of social sciences. "However, these films often have smaller budgets than those helmed by male directors and white directors. So, in a year where more diverse productions were made more accessible to larger audiences through streaming services, the contrast is stark as to what types of films have the big budgets. There is a clear underinvestment of films made by, written by, and led by women and people of color."

Only 338 films were released last year, compared with 987 in 2019.

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