A company in New Zealand that tested four-day work weeks says the experiment was so successful that it wants to make it permanent.

Perpetual Guardian, which helps customers manage their wills and estates, released the results of its two-month trial this week. The company said its employees all reported greater productivity, better work-life balance and lower stress levels from working one less day a week.

The employees — more than 240 of them — were still paid for five days a week during the experiment, which ran from the beginning of March to the end of April. The trial was conducted by outside researchers.

"It was just a theory, something I thought I wanted to try because I wanted to create a better environment for my team," Perpetual Guardian CEO Andrew Barnes told CNN. "I'm humbled that my team has responded, and they went beyond my wildest dreams."

In a survey taken late last year, only 54% of respondents said they felt able to manage their work-life balance. After the trial, that number jumped to 78%.

Staff stress levels also decreased by around 7%, while metrics used to measure team engagement rose around 20% on average.

Related: New Zealand is going to start taxing tourists

The key to the experiment's success was the staff input, said Jarrod Haar of the Auckland University of Technology, one of the researchers who conducted the experiment.

"They were given the freedom to redesign things," Haar said. The experiment could be a model for other workplaces and become "a revolutionary way to work," he added.

Barnes said employees became more productive, spending less time on social media or non-work activity. One employee even told the CEO that he stopped looking at emails from his wife about an ongoing apartment search during work hours.

"Why am I not paying based on output?" Barnes said. "Why am I paying for days in the office?"

Employees offered other ideas on measuring productivity, like having small flags to place on their desks when they didn't want to be disturbed.

Related: Women could boost Asian economies by $4.5 trillion

The experiment is particularly significant in New Zealand, which has low labor productivity compared to other countries, according to the Organization for Economic Co-operation and Development.

Barnes has recommended to his company's board that a four-day work week be made permanent, and says it could serve as an example for other firms around the world.

"What happens is you get a motivated, energized, stimulated, loyal work force," he said. "I have ended up with statistics that indicate my staff are fiercely proud of the company they work for because it gives a damn."