Investors in movie derivatives should perhaps be warned to watch the film The Producers, in which an accountant determines bad shows make more money than good ones.

Veriana, a media company, plans to set up a movie derivatives exchange allowing studios to mitigate financial risk and investors to trade in the success of a film. Hollywood accounting, though, has an infamous history. In a 2007 lawsuit, now dropped, Tom Hanks claimed co-financiers of My Big Fat Greek Wedding had calculated the film’s gross receipts to be a quarter less than the $370m tracking firm Mojo reported. And in 2004, strong sales of The Matrix swelled producer Village Roadshow’s coffers, yet cross-departmental charges caused a divisional loss. For investors craving certainty, movie derivatives might not be a Raging Bull.