In CR, right click the field on the report, select the formatting option. From there, select the Customize button. There should be an option there some where that tells CR to "Display 0 when NULL" .... some something to that effect. If it's not in the "Customize" options area, it's under the accounting tab .... poke around, I know I've seen it before.
This is for CR9 but should be similar for other versions.... from the File menu select Report Options. Check the boxes labelled Convert Database NULL Values to Default and Convert Other NULL Values to Default.
For numeric fields this should display a zero when NULL, and for text fields will display an empty string.
Pete
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