Blank cell creating a Zero value and messing up chart

[Met Fan]

I have a range of data I use for a chart. Since it gets its data daily from other sheets the future sheet dates should have a blank value. The formula I had to grab the info for tomorrows data is:

=IF(ISERROR('9.26'!$L$10:$M$10)," ",'9.26'!$L$10:$M$10)

I need to us an IF(ISERROR formula because the cells L10:M10 in the worksheet 9.26 are merged and contain a formula. When I look at the chart the data point is a zero value and I want it to be blank.

Can anyone help?

 

[Datsmart]

Try this:
=IF(ISERROR('9.26'!$L$10:$M$10),NA(),'9.26'!$L$10:$M$10)
The NA() should not show a value where the " " does.

 

[Met Fan]

Thanks - that worked!