Excel--Charts--Pie Charts--PLOT AREA

Hello,

How do I  resize the PLOT AREA, not the Chart Area, of a Pie Chart? I have several pages of Pie Charts in an Excel document. I have already resized the Chart Area for all of the pie charts, making them consistent. However, I need to resize the PLOT AREA and make this proportional/even among ALL the pie charts in the document. This resizing of the PLOT AREA for Pie Charts isn't the same as bar graphs. So how do I complete this task?

Thank you so much!