Try using a calculated field as
Calc = IF sum(Value) = 0 THen NULL Else Sum (value) end
Thanks for your reply. Do you also know a way without creating calculated fields? I would expect it should be possible with formatting. The downside for me for using calculated fields, is that there are multiple sheets (different datasources) with multiple columns with the same issue, such that this would mean creating about 30 calculated fields. Creates a bit of a mess ;-).
In such case use the custom format.
In custom format you can give 3 parameters for +ve; -ve; and 0.
For 0 use "".
Or even you can also give any other text like NA.