Soluton 1 :"Decimal Places" in currency settings.I think if you are dealing with Monetary fields, then you dont need any code change, only need to set proper"Decimal Places" in currency settings
Solution 2: It will impact database table coumn propertiesYou can add your field with Decimal Accuracy with custom codes, and then precise as needed.
Solution 3 : It will be system wide and only for viewing purpose.All values of pivot is renderer after formating with a js method named , getFormattedValue(cell)The field could be relational(m2o) or non relational (char , var char)Lets say you are trying to see sales value , then it would be the toal amount grouped by your preferable measures.
So before rendering model sends the value to the pivot_rendererwhich uses the registry formater / So you need to bring changes to the registry category named "formatters"

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