2.2.4.3 Value Metadata
Value metadata is metadata associated with the value of a particular cell. Value metadata is associated with a cell through a formula (section 2.2.2) containing a single special function, _xlfn.COMPOUNDVALUE, whose single mandatory argument references a metadata block record (section 2.2.4.4)<18>.
The only value metadata type represented in BIFF8 is MDX metadata (section 2.2.4.5).