If you want empty column in your report
go to :-
Edit Report In "criteria" go to ---> "column properties" in the report column which you want make it empty column
Select "Data Format" in the column properties tab ---> check the "check box" and
In "Treat text As" drop down box select "Custom Text Format" in the drop down box
and in "Custom Text Format" text box Remove the "@ sign"
Now click ok and see result it show empty column...
What Bala is going is correct. A little bit information adding.
You are having the column as in number format know so go to column properties --> Number Format ---> check in Over ride default data format--> below that treat number as drop down to custom and add 0 or NULL.
Check in the report you will get a changes.
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