You could use autofilter to hide the rows of those with a zero value.
Or formula as described here,
I have a pie-chart which refers to 50 rows of data. There are never any
more than 5 or 6 with any values, and the pie chart looks fine...
EXCEPT... the legend shows all 50 entries. Is there a way to tell it to
ignore (or not display) any entries that have a zero value (and
therefore do not show in the pie)?
Andy Pope, Microsoft MVP - Excel