If you use a SQL Report as a Tab in B1 Usability Package and use Sum and Collaps level you will see that the total are wrong.
We have logged this to SAP support but unfortunately they refuse to fix this:
Answer from SAP :-(
Dear Mr. Rasmus Wulff Jensen,
After detailed investigation of the Business Impact and the Product Strategy we came to the decision that the correction of the system behaviour is not feasible in the currently supported versions of SAP Business One. The error has been recorded and is a candidate to be fixed in a future version.
Please see SAP Notes 968358 and 2429253 (SAP note created to describe the issue will be released soon) for further information.
There is unfortunately no workaround and if you feel like us that this should be fixed I recommend you vote on it in SAP Idea Place: https://influence.sap.com/sap/ino/#/idea/141838