https://en.wikipedia.org/wiki/Basis_point
edit: My bad. Correct character, incorrect description. It is indeed "ten thousand".
Unicode U+2031 ‱ is actually the per ten thousand sign (check its character name).
Unicode U+2030 ‰ is the per thousand (or "per mille") sign.
https://en.wikipedia.org/wiki/Basis_point
edit: My bad. Correct character, incorrect description. It is indeed "ten thousand".