2.2.2.6 Formula Elements
Some Ptgs (section 2.5.98.16) require extra data that is not stored in the Rgce (section 2.5.98.88). When an Rgce contains one or more of these Ptgs, the containing formula structure includes an RgbExtra (section 2.5.98.87) containing the data for those Ptgs. The size of these components is specified by the RgbExtra structures. The Ptgs do not contain an offset into the RgbExtra for their data. The Ptgs that require a corresponding structure in RgbExtra are specified in RgbExtra.