A Pivot Chart is a chart (section 2.2.3.3)
that uses a PivotTable (section 2.2.5) as a data
source. The SXViewLink (section 2.4.316), PivotChartBits
(section 2.4.196), and SBaseRef
(section 2.4.242) records in
the chart sheet (section 2.2.3.1) specify
the PivotTable.