Hi @Yun,
Not sure about your original data, let's set it like shown below.
And then you may use expression to get what you want.
=IIF(Fields!data.Value * 100 = CINT(Fields!data.Value*100), format(Fields!data.Value,"0%") , format(Fields!data.Value,"0.0%"))
Regards,
Zoe Hui
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