Check the field expression to

IIF(EMPTY(myfield), NULL, myfield)

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>again to mess up with you people, i have a simple question, i have a record that im sending to the report, say i have 5 records with fields a,b,c
>now on the report form i want to count the number of records where field a is not empty and omit those who are, however, count in the form seems to act different, correct me if im wrong, does it count the total no. of records sent into the report form? if so, is there a way to add an expression or a workaround just to count for fields not empty?
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