Cities' Bedtimes Revealed in One Map

— -- Whether it's because of sports broadcast schedules or circadian rhythms, people in the western United States seem to hit the sack earlier than people in the East.

Tech-device maker Jawbone released sleep map graphics that it says show what time people go to sleep, by county, and how long they sleep.

Brooklyn, or Kings County, stays up the latest, until 12:07 a.m., and the earliest to bed are Hawaiian Islands Maui and Kauai at 10:31 p.m. and 10: 33 p.m., respectively, Jawbone said.

People who live in cities don't get as much sleep as those in suburban and rural counties, Jawbone said.

"No major city in the United States averages above the [National Institutes of Health]-recommended seven hours of sleep per night," according to the San Francisco company's blog.

The nonscientific survey was based on over 1 million people wearing Jawbone's health and activity tracker UP. Jawbone said it blended less-populous counties with neighboring counties "to generate significant results."

"This technique revealed patterns at finer granularity than the state level, such as time zone boundaries. All data is anonymized and presented in aggregate," Jawbone said on its blog.