Besides researching and exploring the admin portal on my own, I have sought help from your support group in generating a report of SMS messages made by our users. I was told there is no such reporting capbility.
Clicking on Admin Portal->Billing->Paid SMS Usage:View Log yields no records. Prior to this search, I sent a text message from my direct, to my cell.
Perhaps I'm doing something incorrectly? If not, this capability is needed to keep track of the count of SMS messages.