I have entered a function:

=SUM(IF(ISBLANK(F3:F39),E3:E39,0))

This is supposed sum the values in E3:E39 where the corresponding cell
in F3:F39 is blank. When I open the formula editor box, the formula
result displays correctly, but the cell only displays 0. Any ideas?
Here's some sample data:

Withhold Amt. Released
$750.00
$200.00 2/3/2006
$300.00


Total Withholding: $1,050.00 (supposed to be)

The total withholding is displaying 0 in the cell but in the formula
editor dialog box the formula result is shown as the correct 1050.

Any ideas why the formula editor would show correct amount while the
cell only shows 0?

Thanks,
Brandon