<f> (Formula)

This element specifies a reference to source of the data contained in this chart. This shall be used by the spreadsheet application only. A presentation, or word processing application should use the externalData element.

This reference is in the form of a book, sheet, and cell reference or a book, optional sheet, and defined name reference. This reference does not include the equals sign. [Example:

<c:cat>
  <c:strRef>
    <c:f>Sheet1!$A$1:$C$1</c:f>
    <c:strCache>
…
    </c:strCache>
  </c:strRef>
</c:cat>

The above example shows a formula reference used for the string cahce. In this case the series names, which are referenced by the formula element, are in cells A1, B1, and C1.

The possible values for this element are defined by the XML Schema string datatype.