Overall, Roberts, 32, who won a Best Actress Oscar last year for her role in "Erin Brockovich," ranked No. 12 on the trade paper's list.
Despite her lofty position, however, Roberts came in at No. 3 on the same list last year. Her only film role this year, in Steven Soderbergh's "Full Frontal," was a flop.
The second most powerful actress is Cameron Diaz, 30, who apparently can also pull down $20 million for a film role. She will be seen soon, costarring with Leonardo DiCaprio in Martin Scorsese's long-awaited epic "Gangs of New York."
Drew Barrymore, Reese Witherspoon and Jodie Foster all made the Top 10 actresses list, earning $10 million per film.
Sandra Bullock, who's paid between $8 million and $10 million a film, came in at No. 6, and J.Lo is No. 9 thanks to her $8 million salary.
The overall power list is topped by Sherry Lansing, the chairman of Paramount Pictures. Other notable rankings: Madonna at No. 60, and Harry Potter author J.K. Rowling, who is No. 64.
JOSH & FERGIE: ROCKED BY SCANDAL
Did he cheat with a stripper?
Married less than a year, the couple denies an Atlanta woman’s claims that she and Josh had a fling
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