How can I format a value in percentage with 1 decimal place on a pie chart label with concatenated valued. The value comes from my SQL query which is float then I use FORMATPERCENT in SSRS Expression.
=Fields!Category.Value & " - " & "(" & FormatPercent(Fields!CallCountPercent.Value) & ")"
Try:
=Fields!Category.Value & " - " & "(" & Format(Fields!CallCountPercent.Value,"P1") & ")"