Financial Tax Register - Credit Memo showing **** for Taxable Amount

We are in the process of upgrading from 11.5.10 to 12.1.3.  When I run the Financial Tax Register report some, not all, of our credit memos are showing ***** for the taxable amount field.  It then has **** in the Report Total in the Taxable Amount column.  Has anyone come across this?  I cannot find anything else out there referencing this.