A new study revealing that chief executives' pay has soared by 10% over the past year has sparked outrage.
An annual survey by analysts Manifest and pay consultants MM&K showed that pay for performance "was still not working", with average chief executives' pay increasing to over £4.2m.
Research among more than 580 leading companies revealed that the UK's top 100 chief executives were paid £425m in 2012, up by £45m, or 10%, from 2011.
Top pay has pulled away even further from earnings in smaller firms.
The increased payments were almost entirely due to Long Term Incentive Plan (LTIP) payouts.
"With the FTSE 100 Index reaching record highs (it recently hit 6,900), it's not surprising that the average top 100 chief executive officer saw their total pay rise by 10% to £4.25m," said the report.
"The CEO pay increase is entirely due to increases in amounts of so-called "performance-related pay" which is linked to share price movements.
"While the average basic salary saw no change in 2012 over 2011, this is due to the lower pay of new appointees and changes to the make-up of the top 100 index. On the other hand, Long Term Incentive Plan (LTIP) payouts rose 40%."
TUC general secretary Frances O'Grady said: "With wage growth falling to its lowest level in decades, it's outrageous that top CEO pay is now rising 10 times faster than average wages."
Len McCluskey, Unite general secretary said: "These figures show that it's business as usual for the super rich. Despite a flatlining economy, the bonanza in Britain's boardrooms continues."