There isn’t one. There is no governing body on language usage, grammar, or punctuation, at least as far as English is concerned. (The Academie Francaise does make edicts on what is acceptable in French, and what is not.)
Language is considered living and evolving.
Most punctuation was decided upon by typesetters. If the need for another punctuation mark arises, it would nowadays be decided by a font designer and whatever keyboard manufacturer agrees to design a keystroke for it. That is why some but not all keyboards have € for the Euro.