The first large-scale study of a four-day workweek has come to a startling close: Not one of the 33 participating companies is returning to a standard five-day schedule.

Data released Tuesday show the organizations involved registered gains in revenue and employee productivity, as well as drops in absenteeism and turnover. Workers on a four-day schedule also were more inclined to work from the office than home. 

“This is important because the two-day weekend is not working for people,” said lead researcher Juliet Schor, an economist and sociologist at Boston College who partnered with counterparts at University College Dublin and Cambridge University. “In many countries, we have a workweek that was enshrined in 1938, and it doesn’t mesh with contemporary life. For the well being of people who have jobs, it’s critical that we address the structure of the work week.”

The study is the first from a series of pilots coordinated by the New Zealand-based nonprofit advocacy group 4 Day Week Global and involving dozens of companies in ongoing six-month pilots. A US and Canadian trial began last month, and a pilot of mostly European and South African organizations begins in February. With each iteration, the researchers will adjust their data collection, including long-term tracking of how organizations fare with lighter schedules. 4 Day Week Global doesn’t fund the research.

The initial data were collected from businesses and organizations in the US, Ireland and Australia, tracking 969 employees over a 10-month period as they reduced their workweeks by an average of six hours with no change in pay. They varied from a restaurant chain in the southwest U.S. to an Ohio-based custom RV builder to a climate nonprofit in Dublin.