This figure compares with a difference between the sexes of only 3% in 2004 and 2005, leading to the seemingly obvious conclusion that not only are men better at their work than women, they are improving while women slack off.
The statistics are part of research into pay in the marketing industry, commissioned by the Chartered Institute of Marketing and carried out by remuneration specialists Croner Reward.
They reveal that at nearly all levels of the profession, the difference between the salaries of men and women is growing, but it is at director level where the difference is most pronounced. This year, a woman director's average pay has risen to £61,000, but men can expect to earn £75,000.
Since the Equal Pay Act came into force in the UK 30 years ago, it is illegal to pay women less than men for doing the same work. Some reasons given for the disparity in pay levels are the different life choices made by men and women, and women not being as aggressive in pay negotiations as men.
However, bodies like the Equal Opportunities Commission argue that wholesale reviews of employers' pay systems are needed more than better negotiating skills for women.
The CIM survey revealed that, on the whole, marketers are happy with their lot. One-fifth of those surveyed believe their pay is above the market average, a rise on last year, and almost two-thirds of people believe they are paid the going rate.
Other trends revealed by the research are that bonuses are making up a bigger percentage of all marketers' pay packets and have risen by an average of 35% when looked at across all levels.
It also showed that senior marketers were scoring bigger pay rises than their junior and middle-management colleagues. Earnings of directors went up by 7.5% compared with only 2.2% for the most junior staff.
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