A new study co-authored by a UChicago scholar demonstrates that giving sales associates more stable schedules leads to increased sales and labor productivity.

Working in partnership with retailer The Gap, the interdisciplinary research is the first randomized, controlled experiment designed to shift low-wage, hourly jobs toward more stable schedules. The intervention produced a high return on investment, increasing median sales by 7 percent and labor productivity by 5 percent—challenging the widely held assumption that schedule instability for part-time and full-time employees is inevitable in the volatile retail sector.

“Scheduling practices in retail jobs are often characterized by hours that fluctuate week to week and day to day. This makes it hard to fulfill responsibilities on and off the job,” said study co-author Susan Lambert, associate professor of the University of Chicago’s School of Social Service Administration. “The results suggest that employers can improve work schedules in hourly jobs and also meet their business goals.”

The researchers define a “stable” schedule in terms of both the consistency and predictability in the number and timing of hours employees work each week. The study, which included Prof. Joan C. Williams of the University of California and Assoc. Prof. Saravanan Kesavan of the University of North Carolina, was conducted in 28 stores in the San Francisco and Chicago areas, running from November 2015 to August 2016.

In the experimental group, which comprised a randomized group of 19 of the 28 assigned stores, managers were told to give more consistent daily and weekly schedules to workers and often allowed to marginally increase workers’ total number of payroll hours.

“To date, what we find is that the move to more stable schedules improved retention among workers with more seniority who have greater knowledge of products and processes,” Lambert said. “This helps explain the productivity boost.”

In the report, the group recommends employers “take the leap to more stable scheduling” because of the business benefits, as well as the fact that several cities, including San Francisco, Seattle and New York City, have passed scheduling legislation, with comparable legislation pending in at least 13 additional municipalities.

“Continued pressure from legislatures and lawsuits mean that the time is right for employers to take the initiative to improve schedule stability in ways that work for them,” the report concluded.

Lambert praised the Gap for its commitment to the research and its willingness to try new approaches to scheduling hourly workers.

“The Gap is very much committed to making a profit and views its employees as core to that,” Lambert said. “They know that unstable work schedules make it difficult for employees to do their job well and to plan their life outside of work.”

Funding: The Stable Scheduling Study was supported by grants from the W.K. Kellogg Foundation, the Washington Center for Equitable Growth, the Robert Wood Johnson Foundation, the Institute of International Education in collaboration with the Ford Foundation, Center for Popular Democracy, the Suzanne M. Nora Johnson and David G. Johnson Foundation, and the Gap.