More than 3,000 workers at 70 companies around the world are testing out a pilot program over the next six months that shortens the work week to four days, without cutting pay. The trial was organized in part by Cambridge University, Oxford University, and Boston College. Researchers will be analyzing how employees respond to an extra day off in terms of stress and burnout, work-life balance, health, and sleep, among other factors. The chief executive of Charity Bank, which is taking part in the program, said he firmly believes that a four-day week with no change to salary or benefits will "create a happier workforce" and will have an "equally positive impact" on productivity and customer experience.