Loss of formatting is a known problem with pivot charts. There's
information in the following MSKB article, which suggests recording a
macro as you apply the formatting:

Changing a PivotChart removes series formatting in Excel
http://support.microsoft.com/?id=215904

Nico wrote:
I am using pivot chart with calculated fields, on which I did some quite
sophisticated formatting (combination chart stacked bar / dot plot with
secondary axis ; bar & plot area & grid colors ; labels ; axis & chart
titles).
When I click the "refresh" (!) button to update the data, the chart
formatting is lost and the chart reverts to the default formatting (stacked
bar chart with all series)
Is there any way to "memorize" the chart formatting on a pivot chart ?


--
Debra Dalgleish
Contextures
http://www.contextures.com/tiptech.html