File - In this April 30, 2014 file photo, Facebook CEO Mark Zuckerberg gestures while delivering the keynote address at the f8 Facebook Developer Conference in San Francisco. Zuckerberg and his wife, Priscilla Chan, are donating $120 million over the next five years to the San Francisco Bay Areaâs public school system. The gift is the biggest allocation to date of the more than $1 billion in Facebook stock the couple pledged last year to the nonprofit Silicon Valley Community Foundation. (AP Photo/Ben Margot, file)

American Facebook members spend an average of 40 minutes per day on the social network -- about as much time as Americans devote to household chores and personal grooming.

Mark Zuckerberg shared the statistic on Facebook usage during an earnings call Wednesday, and qualified it by saying he still sees ample room for growth. Some might balk at the notion that Americans pass about as much time peering at each other on the social network as we do on habits like showering -- we average 42 minutes of grooming per day during the week, according to the Bureau of Labor Statistics. But the Facebook CEO pointed out that Americans spend a full nine hours each day engaging with all forms of digital media, and hinted he hopes to claim a larger share.