3.2.3.1.6 Chart formulas

Chart formulas define data ranges and values used by charts, such as chart ranges, series ranges, series titles, and axis titles.

A chart formula shall be either a 3-D reference or a constant.

 chart-formula=
 chart_ref |
 "(", chart-ref, ",", chart-ref, {",", chart-ref}, ")"
 chart_ref = 
 external-cell-reference |
 external-name ;