Miss format setting in chart like below. % mark is missing even enabled "Show in Percent (%)" on Number tab.
Expression A is fine.
This chart has 2 expressions following.
Expression A: IF(Field='A', Sum (A)/1000, Null())
Expression B: IF(Field='B', Sum(B)/1000, Null())
In this case, try to control display/ no display the expression with IF function. Then format settings are gone for second expression.
This is product design at the moment. Please apply above workaround in your application.
We provide "Conditional" option for control to show up expression. Refer following image.
Defined expressions like this.
For conditional option: Field='A'
For expression: Sum(A)/1000
Also need to change expression B. Please refer attached sample qvw.