@Felthry Yes and no. One could "just as easily" compose it from each individual part – ⁰⁄₃ – but one could have done the same for ½, ⅓, ⅔, ¼, ¾, ⅕, ⅖, ⅗, ⅘, ⅙, ⅚, ⅐, ⅛, ⅜, ⅝, ⅞, ⅑, and ⅒ as well, yet those also have distinct codepoints, so there's got to be some logic to it, right?
(Actual answer: Apparently it's somehow useful for rendering baseball statistics. *shrug*)
(Actual snark: And of course, it far surpasses the usefulness of, say, a half-star to go along with ★ and ☆, right?)
@ElectricKeet well the reason was that it's zero thirds, why do you need that? there's no zero halves or anything