Stores the symbol (for example, an asterisk, numeral, section mark) that was displayed in the original document to identify a specific footnote, if this symbol is to be preserved.
For example, it might be useful to store the symbol to disambiguate mis-tagged cases in which an author has stated “see footnote b” or “see footnote 14” in the text, but the “see” note has not been tagged as an <xref> element. When the cross-reference has not been tagged, the normal ID/IDREF connection between footnote and reference is missing, and the only connection between the two is the visually matching symbols (“b” and “14”, respectively).
To preserve a dagger symbol as marking a footnote for a table
... <table-wrap-foot> <fn id="TF1-218" symbol="†"> <p>Data not available or incomplete for this time period.</p></fn> </table-wrap-foot> ...