More than 38% of Indiana residents report that they do not get enough sleep at night, reports the Indy Star.

Hawaii leads the nation when it comes to sleep deprivation. South Dakota residents report getting the most sleep.

Sleep experts say they do not know exactly what lies behind geographic variations in shut-eye. One factor impacting Indiana could be that the state sits on the Western edge of a time zone, said Matthew Weaver, a research fellow in the Division of Sleep and Circadian Disorders at the Brigham and Women’s Hospital, which helped the council develop its new tool for employers.