A new study from University of Maryland sociologists John P. Robinson and Steven Martin suggests that Americans are getting as much, if not more, sleep than they did 40 years ago. This study also made use of time diaries to determine how long Americans were sleeping, as opposed to previous studies that just asked respondents outright.

Key findings from the report:

“Sleep Patterns 1965-1995: There was little change in sleep averages during this period, particularly in comparison to the far larger shifts in time spent on housework, child care and watching TV. ‘The proverbial figure of eight hours per day (56 hours per week) has remained close to the diary norm for those aged 18 to 64 in each national study between 1965 and 1995,’ the report says.”

“Sleep Patterns 2003-2005: The time diaries collected by the federal government on an annual basis between 2003 and 2005 showed rising sleep averages – 8.2 hours on weeknights, 8.9 on Saturday and 9.5 on Sunday, a total increase of about three hours per week.”

“‘While these recent increases are statistically significant, we’re approaching them with some caution,’ says Maryland sociologist Steven Martin, the co-author of Not So Deprived. ‘The numbers didn’t change for more than 30 years. We want to see if these increases hold up in the long-run.'”