Sort in a Pivot Chart

Does anyone know how to sort a bar graph by descending value (actual units), will not let me sort in Pivot table because it has multilple columns (categories)

Not sure what you've tried, see this article or google for "sorting pivot chart" (without quotes):

http://office.microsoft.com/en-ca/excel-help/sort-a-pivottable-or-pivotchart-report-HP005202971.aspx

Yes I read this article as well. The problem is that I have multiple (3) categories in the vertical axis. So when I do a sort in the last column in my pivot table, it only sorts by each individual sub-category, not ALL the sub-categories combined. Does this make sense? I cannot remove this subcategory either because I need to show it in my Pivotchart. I even changed the report layot to tabular form, took out all the subtotals then sorted by largest to smalles butonce again it did not do it at the last level only at the sub catgeory level prior to it.