Dr John Stockton wrote:

ISO 8601:2000 specifies that the separators are hyphens; it does not
give the Unicode encoding. However, IIRC, a dash is not a hyphen.
Mostly, I expect that Unicode 0045 = ISO-7 45 will be used; that's the
well-known keyboard character commonly used for "minus".

It is also the well-known keyboard character commonly used for "hyphen."
Which is why its official Unicode name is HYPHEN-MINUS. And it is given
in hex, U+002D. U+0045 is LATIN CAPITAL LETTER E.

There are other code points used for exclusively hyphen (U+2010) and
minus (U+2212).
--
Michael Hoffman