How lazy are you at work?

One in five Brits admit they never work to the best of their ability in their jobs, according to a survey by tech firm Dropbox.

Nearly three-quarters of the 2,000 people interviewed said that they don't work to the best of their ability even once a week.

Respondents added they think only 68% of colleagues are good at their jobs.

The results come amid weak forecasts for economic productivity in the next five years.

"Fundamentally people have a natural inclination towards laziness and without clear roles and objectives we are drawn towards loafing and free riding," said Brennan Jacoby, a philosopher at cultural institution The School of Life, which conducted the survey with Dropbox.

"Often it's not a lack of motivation causing this, more often it can be a lack of clarity," he added.

"Give team members clear roles and responsibilities and the chances are productivity and happiness will rise."

The UK's poor productivity has been blamed for holding back the UK economy.

In last month's Budget the government's economic watchdog, the Office for Budgetary Responsibility (OBR), said productivity has grown by just 0.2% a year for the past five years, much less than expected.

It also warned productivity will see only weak growth in the next five years.

The Dropbox survey found that construction and emergency service workers have the highest opinion of their colleagues, whilst those in public relations and IT have the lowest.

Dropbox said this might be because sectors such as construction and medicine are "safety-critical" jobs, which require trust to be placed in co-workers to ensure everyone's safety.

It added that the benefits of teamwork are also more apparent and more clearly understood in these roles.

The survey indicated that those in more senior positions had a lower opinion of their colleagues compared with those in entry-level roles.

Managing directors and board-level workers said they believed only 58% of their co-workers were good at their jobs.