Directors of top companies have also seen their total earnings shoot up. A 21 percent jump in total earnings was driven by a 44 percent increase in share-based incentive payments and a 12 percent increase in bonuses. A director now typically earns a total £2.43 million a year, according to IDS, which provides information on U.K. employment issues.
The report comes at a time of increasing frustration over the lack of wage growth in the U.K., despite broader economic expansion. Bank of England Governor Mark Carney has ruled out a rise in interest rates until there is improved wage growth and productivity in the country.
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Over the year to June, increases in directors' basic salaries "remained muted", rising by "just" 2.5 percent, the report said. But this remains below the 1 percent annual wage growth (excluding bonuses) for average full-time employees, according to the U.K.'s Office of National Statistics (ONS).
Painting a stark picture of the widening pay gap between chief executives and the rest of the workforce, IDS' report showed that between 2000 and 2014 the median total earnings for FTSE CEO increased by 278 percent, while the corresponding rise for full-time employees was just 48 percent.
The biggest earnings increases for CEOs were in the media, marketing and telecommunications sectors, followed by transport, leisure and financial services.