the type of footnote marker to identify a footnote. Only one type of footnote
marker must be used for each of the table footnotes and inline footnotes throughout
a
data module. The attribute can have one of the following values:
- "num" (D) -
superscripted numbers will be used
- "sym" - symbols such as asterisk (*) and dagger
(†) will be used
- "alpha" - alpha characters will be used