The definition of insanity is doing the same thing over and over again and expecting a different result. But in the case of the UK economy that is exactly what we have been doing for the past decade.

The ONS figures out earlier this month show a continuation of stagnating productivity growth in the UK. GDP has grown by 0.6% over the same period, which is slower than the increase of 1.0% in total hours worked. In other words, in the UK, the relationship between working time and economic health is one of diminishing returns; increases in working hours are not having the impact on economic growth they are expected to have.

However, when we lift up the bonnet and take a closer look at the statistics, something does not quite add up. Despite stagnating productivity, the intensity of work has steadily increased over the past five years. We are working harder and faster than any point in the past 30 years. Rather than freeing us up and making work easier for us, new technologies have made it increasingly easy to schedule and fill up the working day with tasks, as well as to contact people outside of working hours using e-mail and mobile phones. Automated scheduling has also resulted in less rest as every instance of free time is filled with something “productive” to do. In the workplace, people are increasingly seen as machines, out of which every ounce of productivity can be squeezed.

Of course, we are not machines, and this attitude within work has unsurprisingly turned out to have had catastrophic impacts on workers. This month’s release of HSE statistics show that the total number of days lost to work related stress, depression or anxiety stands at 15.4million, an increase of nearly three million on last year’s statistics, and the third year in a row it has increased. One in four of all sick days lost in the UK are as a direct result of workload. This is a crisis in work.

And like any phenomenon in the UK, these statistics are highly gendered. Women are far more likely to suffer from work related stress anxiety and depression than their male counterparts. A major part of this is because of the ‘second shift’ women do at home. In 2015, women provided 74% of all childcare time in the UK and spent, on average, 26 hours a week doing unpaid domestic labour, including cooking and cleaning. Since the 1990s, improvements in the gendered division of labour have stalled – the number of hours of unpaid work women do each week is roughly the same as it was 20 years ago.

Our model of work is literally making us sick; it is exacerbating already significant gender inequalities; and despite all that misery, it is not having a positive impact on our economy. What can we do differently?

We only have to look over the English Channel to look at how a different attitude towards working time can reap tremendous rewards. The likes of Germany, the Netherlands, and most of Scandinavia work fewer hours than the UK, yet they all have stronger and more productive economies.

This graph shows clearly that there is no clear positive correlation between hours worked, and GDP per capita; in other words, working more hours does not necessarily result in a stronger economy. In fact, looking across European countries, the opposite appears to be the case: countries which work fewer hours tend to have stronger economies.

At the New Economics Foundation we have long called for shorter and more flexible hours of paid work, firstly in our report 21 Hours and then in our book Time On Our Side. That is why we are now officially supporting the 4 Day Week Campaign, who ​“believe that a 4 Day Week will benefit our society, our economy, our environment and our democracy”. The evidence is certainly building that a shorter working week is a practical solution to a series of interconnected and deeply embedded problems in our society.

The campaign for a four-day week follows in a rich tradition of successful campaigns for the two-day weekend and the eight-hour day. It also asks the question: what is the economy for? Surely the purpose of the economy is to create a good life within it, and have a material basis from which you can be housed and fed – but something our economy is not providing for us is time, which we need. The next stage in economic development should not be to generate more stuff, but to create the conditions in which we can live good lives.

In the first half of the 20th Century, it was broadly assumed that part of the function of the economy was to provide us with more free time. In 1930 John Maynard Keynes famously predicted that technological change and productivity improvements would eventually lead to a 15-hour workweek. Back then time outside of work was intuitively felt to be a good thing in of itself – but now we can also see that the shorter working week carries with it significant social, economic, and environmental benefits as well.

We have constructed an economy which systematically robs us of the time we have, and to make things worse we are not seeing any material benefits in economy which is failing the vast majority of the population. It is time to learn from our European neighbours and our own history and destroy the notion that more hours equals a stronger economy; it doesn’t, and it is causing catastrophic levels of harm.

Aidan Harper is a researcher in work and social policy for the New Economics Foundation