[hawkharris]

What's curious about these statistics is that they seem to measure membership rather than engagement.

Do they account for people who register but neglect their accounts? People who choose to deactivate their accounts but don't know how to permanently delete them?

[cmelbye]

The numbers they report are number of active users, which they define as someone who has used Facebook in the past month. (Of course, I'm not sure if that applies to these particular numbers, which look like they may have been taken from Facebook's advertising tool which tells you an ad's potential reach.)