do not chart cells linked from worksheets that are blank
 

I do not want cells to show up on the chart that are blank. The chart is
reading off boxes that the user needs to see, these boxes are linked to many
different spreadsheets. that will be updated each period but the chart reads
future information as zero until data is entered, just because they are
linked. In he actual linked sheet I have tried no data, I have tried N/A a
dash - but nothing seems to work.