Replace the "" with NA():

=IF(condition,"",something)

=IF(condition,NA(),something)

This will display as #N/A in the formula cell. You can hide that by using
conditional formaating and setting the font color to be the same as the fill
color.

Biff

"mtnw" wrote in message
...
A chart series can truncate a couple of datapoints cleanly if you delete
the
contents of the desired cells. When you use IF() and return a "" or some
other syntaxes to represent an empty cell, the chart series does not
truncate
and your series line deflects to a displayed datapoint value of zero and
does
not truncate the series line.
To have a chart truncate a line cleanly and not display erroneous data
zero
points and their connecting lines, then we need to find out how to tell a
formula such as the IF function to return a real empty cell to the degree
that the clearcontents method does when you hit the delete key. e.g.
=IF(condition,"",something)
the "" does leave the cell *looking* blank but charts think there is
something there!
Any ideas?