Last Updated Mar 1, 2010 2:26 PM EST
The initiative launched by the TUC is designed to highlight research from the organisation that found the number of people working over ten hours a week (or extreme) unpaid overtime has increased over six-fold from 14,000 to nearly 900,000 over the last year.
The union calculates over five million employees clocked up over seven hours unpaid work, which is worth Â£27.4 billion to the UK economy and for those people who work the extreme, ten plus hours, it means effectively, they don't start getting paid until 26 April.
It's a chunk of productivity that probably doesn't figure in many economists calculations, but one that might unexpectedly impact the government's calculations on how many jobs the public sector should shed, as it's these workers who are much more apt to work extra hours for no extra pay.
Over a quarter of public sector workers indulge in extreme overtime, compared to one in six private sector staff, according to the TUC's research.
Teachers and lawyers are the professions most likely to work over ten hours of unpaid overtime and single women are more likely to do so than single men, or couples co-habiting, with or without children.
The figures highlight how much rank-and-file staff are taking on to share the pain of the recession and begs the question how much more will they take?
It also should humble some of the pundits in the private sector who have been baying for massive cuts in the public sector, if those cutbacks mean laying off people who actually provide some of their services for free.
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