During the Industrial Revolution, 10-to-16-hour days were normal. Ford was the first company to experiment with an eight-hour day, and found its workers were more productive not only per hour, but overall. Within two years, their net profit doubled.
If eight-hour days are better than 10-hour ones, could even shorter working hours be even better? Perhaps. For people over 40, research found that a 25-hour work week may be optimal for cognition, while when Sweden recently experimented with six-hour work days, it found that employees had better health and productivity.
This seems borne out by how people behave during the working day. One survey of almost 2,000 full-time office workers in the UK found that people were only productive for 2 hours and 53 minutes out of an eight hour day. The rest of the time was spent checking social media, reading the news, eating, having non-work-related chats with colleagues, and even searching for new jobs.
