From The Hollywood Reporter:
How bad is the decline in actor salaries over the past decade? Despite the huge sums still being raked in by such superstars as Robert Downey Jr. (his $75 million comes from his 7 percent, first-dollar slice of Iron Man 3, as well as his $12 million HTC endorsement deal) and Sandra Bullock (a 15 percent, first-dollar deal on Gravity and about $10 million more for her summer hit The Heat), most actors are feeling a definite squeeze, especially those in the middle.
“If you're [a big star], you're getting well paid,” says one top agent, “but the middle level has been cut out.” Sometimes with a hacksaw. Leonardo DiCaprio made $25 million (including bonuses) for The Wolf of Wall Street, while co-star Jonah Hill got paid $60,000. Granted, that's an extreme example — Hill offered to do the part for scale (and got an Oscar nomination for his trouble).
More here.