Item Movement/Movement History and Item Qty reports

Hi, Does anyone know if there would be a reason for the Item Quantity report to not match the Item Movement History or Item Movement reports?

For testing purposes, I checked out the sample database. If I run the Item Movement and Item Movement History report, they agree that there is quantity

I've checked the off-line inventory already and I can't find any explanation as to why these 2 don't match. The only possible thing I was thinking of was that the initial loading of the database says that there were 12 footballs to start off with. But of course, there's no way for me to verify this as there is no transaction in the tables.

Thanks in advance!