The university’s productivity experts suggest that a four-day working week is better than a five-day one, as employees become more happier and very productive.

These are the results of a six-month experiment in which 5 000 workers in BT call centres reported their happiness on a weekly basis. They were asked to rate their happiness every week on a scale of one to five.

During a four-day working week, employees increased the number of calls fielded, made more sales, were more positive in general and worked better in less time. Customers were also happier.

Associate Professor of Economics and Strategy at Saïd Business School at Oxford University Jan-Emmanuel De Neve told the Telegraph: “I would argue the four-day working week is spot on in terms of finding or striking that right balance between improving the work-life balance and unlocking the happiness potential from that in terms of productivity gains.

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“This outweighs the net reduction in productivity from working a day less,” he said.

According to the study’s findings, the current working standard of employees working five days and rest two days over the weekend doesn’t allow them to fully recharge, while an extended break would allow them to be completely refreshed to face the week.

He told the Telegraph that this is a neurobiological effect of having a shorter week.

“When you are more positive about your job and your life while on the job, it relates to being able to be more productive,” he said.

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Business Insider reports that an eight-week trial conducted in New Zealand earlier this year found that a four-day working week increased teamwork and work engagement and decreased stress.

It says some of the participants in this study had to break out of the trial to keep up with the busy schedule.