How many digital photos are being taken every day/hour/minute?

Is there any way of knowing what happens with those photos - for example:
- how many get printed, 
- how many are uploaded onto photo-sharing sites,
- and how many just sit there unused?  Percentages are fine.

I'd really appreciate a response!  I'm trying to do market research on
digital cameras, and this is just an interesting set of statistics
that would help me a lot.  Thanks!