Keep in mind folks, this is Easter Weekend and today is Good Friday. My guess is a lot of folks are probably doing the family thing.
Also important to keep in mind... a large chunk of the members are late teens / early 20's... and many are in school or college. Thus, many are probably in the middle of finishing up their semester and getting ready for finals, etc.
I would assume that during the summer months, most folks will tend to spend more time outside (and offline) than inside and online.