Not gonna swear to this, but it is possible that for a 3D chart, these two numbers would be different. Also, note that for 3D charts, the plot area is not square (or circular), but polygonal. So I think the height and width define the CONTAINING rectangle whereas the insideheight and insidewidth define the CONTAINED rectangle.
But don't sue me if that ain't it.
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Retired over one year and survived being home all day with the wife. She must really love me.
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