When dealing with sportsbook stats as I know from my experience you need to take into the account the following factors:-
1) The time the game was graded, a bet may of been placed on the last day of the month and graded on the 1st or even 2nd of the following month. This can result in a flucturation in your stats.
2) Chargebacks do happen and need to be noted. Once again this will affect your stats.
3) Some games are future bets and the results have not yet been finalized. This also will affect your stats.
This should hopefully clarify some things for the sportsbook affiliates. It is important to also note that your stats can be affected in a positive way.