I know pivot charts are used to "summarize" the data. but if i have a table like

A 20 24 83.33
B 16 24 66.66

where the fourth column is calcuating the 2nd/3rd * 100. basically percentage.
Now if i want to draw a graph its easy, but if i want it to be drawn through a pivot table ? ie a pivot chart how would i do it. Now my question is in what format my data should be so that i can draw a similar graph which shows A and B and their percentages.
NOw i know i can use calculate field , but you see eventually i want it to be published on "share point" where the only graphing component is pivot chart.owc that component doesnt support the concept of calculate field. or i may be wrong. iF it does please tell me how to use it. ?