In a recent FT Magazine article on the crisis in workplace depression — said by the World Health Organization to cost the global economy $1tn a year in lost productivity — a US workplace mental health specialist, Donna Hardaker of Sutter Health, commented: “This is not about buying Fitbits for employees and teaching them deep breathing so we can pile more work on them.”

This was read with particular interest in the village of North Newbald, Yorkshire, because it is here that a tech device that might be considered a mental health Fitbit for the workplace has been developed.

Moodbeam, a £50 subscription-free, wearable, mood-logging device, is being piloted for employees at Barclays Bank, by two Premier League football clubs, a global TV channel, a law firm, a UK Olympic team and a big engineering company. The NHS in East Yorkshire is trialling it for several mental health problems, as are two universities and a private school. Interest is also coming from the US, Australia and elsewhere.

Moodbeam’s principle is simple. It is a wristband with two buttons, one yellow and one blue. Wearers press the yellow one when they feel happy, the blue when they feel sad. The seemingly facile information harvested is uploaded to a phone app and Moodbeam’s own cloud.

The inventors claim it is not only hugely helpful and empowering to users and their families and carers — but also to mental health professionals, since no such self -generated data set on happiness previously existed. The inventors believe that anonymised data on how happy people are feeling in real time at specific locations could be gold dust for enterprises such as airports and theme parks.

Moodbeam’s genesis could be a storyline from The Archers, the popular BBC radio rural life drama, which loves up-to-date non-farming themes.

A journalist living in North Newbald, Christina Colmer McHugh, discovered that her daughter was being bullied at the village school. The teachers were dealing with it, but Ms McHugh yearned to know how her child was feeling during the day. Without any tech background, Ms McHugh dreamt up the idea for a wearable mood tracker.

Cue the second character in the story, fellow villager Jonathan Elvidge, a former telephone engineer who in the 1990s founded the Gadget Shop chain and soon found himself on UK rich lists. Then, after a complicated commercial dispute, he came close to personal bankruptcy, losing his income and his relationship.But he built it all up again in a new consumer tech retailer, Red5, sold that and at 52 had semi-retired, apart from advising local start-ups.

So Mr Elvidge knew a thing or two about both tech and workplace mental health. Early in his Gadget Shop days, he was in the habit of vomiting from stress every morning.

He was on holiday with his extended family celebrating his second-time-round wealth when Ms McHugh called him with her idea. It appealed so much that they became business partners. The result, three years and £475,000 investment later, is Moodbeam, which has been selected to star in the British pavilion at January’s Consumer Electronics Show in Las Vegas.

I wondered, however, if wearing a visible device that announces you have mental health concerns might not be thought uncool by the likes of bank managers, elite athletes and students. But Moodbeam’s creators say I am misjudging the mood of generations new to the workforce.

“What we’re discovering is that, for younger people, wearing it stands for something — that I am open about my wellbeing and mental health,” Mr Elvidge says. “People at the boarding school where we introduced it positively wanted to wear their Moodbeam as a visible thing.”

“Millennials are coming through and employers are discovering there’s an expectation on them to cater for their mental wellbeing as well as physical needs, or holiday entitlements,” Ms McHugh says. “Interviewees are saying, ‘What can you do for me if I’m struggling with mental health? It’s a generational thing.”