Hi @sumeeng ,
Could you please let us know how did you get the Values column?
Such as using a measure that you created in Power Pivot to calculate the sum of each item. Or this column just show the text with "Sum of XXXXXXX <Number>".
It's better to share us with a simple sample. Thanks for your understanding.
For general pivot table, to get the grand total, you can
select the pivot table, go to Design tab > Layout group > Grand Totals, choose "On for Rows and Columns".
Any updates, welcome to post back.
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