In cost accounting, there is the concept of the break-even. This is when cost and revenue are equal. (http://en.wikipedia.org/wiki/Break_even_analysis
So, for a movie like "Man of Steel", this is $225 million (production budget=gross profits). This film has reached the break-even stage.
For the film to be successful, it needs to make $450 million, which is twice the budget. This will cover the cost of marketing and distribution.
The formula for a film is,
Negative Cost=Development Cost+Pre-Production Cost+Production Cost+Post Production Cost
Negative Cost is known aka as "production budget". Man of Steel was $225 million.