Varying weekly work hours and earnings instability in the Great Recession.

Unstable work schedules are increasingly a prominent stratification outcome, particularly for low-wage workers. Nationally representative and longitudinal research on the topic is limited, however. This article examines varying numbers of weekly work hours among hourly workers, their increase during the Great Recession of the late 2000s, and their impact on growing earnings instability. Using data from the Survey of Income and Program Participation (SIPP), the cumulative probability of ever reporting varying hours among hourly workers increased from 36 percent between 2004 and 2007 to 46 percent between 2008 and 2012. Changes in state-level economic conditions, particularly state-level unemployment rates and economic growth, largely explain the increase in varying hours, consistent with arguments that employers pass the costs of volatile demand onto workers. Finally, variance function regressions show the growth of varying hours accounts for the significant increase in earnings instability from 2004-7 to 2008-12.