The so-called "normal" 40-hour working week appears to be a thing of the past, the 2013 Census indicates.
Data from Statistics NZ shows that out of the 1.9 million people aged over 15 who completed the "hours worked" section of the survey, just 595,000 worked a traditional 40 hours a week in their main job.
Almost 141,000 people worked 45 hours, and 153,000 said they worked 50 hours a week. More than 19,000 people worked 70 hours a week, and 426 people unbelievably claimed to work 168 hours a week — which means they got no sleep, rest or ate a meal.
However, people who worked between 41 and 80 hours a week totalled more than a million, and this figure does not include any hours worked in secondary jobs — something two million people have.
But does working more than 40 hours a week translate into higher productivity? A white paper by the New Zealand Productivity Commission shows that Kiwis put in plenty of hours at work but lag behind other countries in the amount of goods and services they produce.
Its report, published in September last year, says that from the mid-1990s, New Zealand has enjoyed periods of good productivity growth — such as between the mid to late 1990s — but overall, productivity performance has been poor compared with other developed economies.
"Indeed, for a number of decades, New Zealand's labour productivity has been falling behind other OECD countries," say Paul Conway and Lisa Meehan, the report's authors. "Labour productivity growth has also slowed considerably in New Zealand in the 2000s compared with the 1990s.
"So as well as having a low level of productivity, New Zealand also has one of the lowest rates of productivity growth in the OECD. This is unusual internationally and raises serious concerns."
Kiwis work about 15 per cent longer than the OECD average, but produce about 20 per cent less output for every hour worked.
"It is because of this poor labour productivity performance that GDP and average incomes per person are low in New Zealand," the report says.
But low productivity does not necessarily mean we are a country of lazybones. In April, a working paper titled An International Perspective on New Zealand's Productivity Paradox pointed to a lack of research and development investment as one of the reasons for the country's low productivity.
OECD economists Alain de Serres, Naomitsu Yashiro and Herve Boulhol, say that weaknesses in our international connections, and an under-investment in knowledge-based capital are "key potential causes of the productivity gap".
There are some things we can't change or fix quickly, but would a shorter working day help raise productivity? It's an idea dating back half a century that is being trialled in Sweden, where local government is experimenting with a six-hour working day — and paying staff for eight.
It is based on a scheme that cereal maker Kellogg started in 1930 but abandoned in 1985, despite protests from some of its staff who fought to hang on to the system.
It was at the start of the Depression that the firm swapped its eight-hour shifts for six-hour ones. Staff who had been "let go" during cost-cutting at its Michigan plant in the United States were offered their jobs back, and productivity soared.
In his book, Kellogg's Six Hour Day, author Benjamin Hunnicutt says the firm's management insisted that six-hour shifts would revolutionise society by moving the balance of time from work to leisure — from economic concerns to the challenge of freedom.
And now Sweden's second-largest city, Gothenburg, is experimenting with the idea. Half the city's government workers will work six-hour days while the other half continue with an eight-hour working day.
The scheme was proposed by the country's Left Party and supported by the Green and Liberal parties. The results will help decide if a six-hour day will be adopted more widely.
The goal, says the Left Party, is a "healthier and happier staff".
The concept is something that Michael Barnett, chief executive of the Auckland Chamber of Commerce, thinks is a great idea. "I'd love that," he says. "I think some firms do work towards that, in that they are not fussed about their staff being at their desk between certain hours — they are more results-focused, they look at the output that they want.
"I don't expect my sales people to be in the office at certain times and I don't track them down every minute of the day."
Barnett says reasons for New Zealand's longer working hours and lower productivity, when compared with other OECD countries, come down to a lack of staff training, low investment in new technology, and clogged roads.
"Too many firms do not invest enough in their people or technology," he says.
"If we have the right technology and the right training, then people are going to be able to perform better."
• Steve Hart is a freelance journalist.