Film Revenues and Piracy

Here's are some interesting numbers and commentary on last year's film revenues. It seems that the largest increase in film revenues has come in the countries that have the most piracy (Brazil, China, India). Especially interesting is the method that the film industry uses to calculate the losses it has suffered as a result of piracy:

Piracy loss calculations are based on the number of legitimate movies - movie tickets and legitimate DVDs - consumers would have purchased if pirated versions were not available.

Not exactly the method that I would use... How do you calculate this? Any ideas?