Last week the actress Jennifer Lawrence provided us with one of the best examples of why pay transparency is essential. Her article published in Lenny Letter, the feminist newsletter launched by the actress Lena Dunham, revealed her feelings of the existence of a significant gender pay gap in Hollywood.

Lawrence was a victim of the notorious Sony hack in 2014 where extremely sensitive details of Hollywood stars pay, conditions and negotiations were leaked. The hack revealed that she and her female colleague, Amy Adams, were getting paid significantly less than her male co-stars.

Lawrence gave a compelling explanation why she felt she’d ‘failed’ to negotiate better conditions. Clearly she can’t be accused of failing at such negotiations. Rather it reveals how differently men and women approach such matters as negotiating fair pay. Lawrence said she didn’t wish to present herself as ‘difficult’ or ‘spoiled’.

Unsurprisingly such a thought didn’t cross the minds of her male counterparts all of whom secured significantly larger sums or money. Lawrence notes that rather than be accused of being a ‘spoiled brat’, as a different leaked email described a female producer, her male colleagues were likely to have been commended for being ‘fierce’ or ‘tactical’.

It was not until she saw the payroll following the Sony hack she realised that every man she was working with didn’t worry about being described in such a way.

Lawrence is a capable, talented and lauded actor (she is of course an academy award winner) so why exactly was she paid significantly less than her male colleagues? Her article reveals as much about ingrained chauvinism, not exclusive to the Hollywood hills by any means, as it does about the gender pay gap more generally.

It also illustrates that women and men negotiate in hugely different ways. In a perverse way senior executives are used to aggressive or robust demands, in fact most seem more at ease with such an approach. Conversely they are uncomfortable with a more considered or less confrontational style it would seem.

It is appalling that in 2015 a female actor is paid significantly less than her male counterpart for doing the same work.

The inadvertent revelation of Lawrence’s story has unearthed the huge gender inequality which still exists in the film industry, business and many other areas of employment. What more evidence of its existence do we need?