I've recently noticed that in Wikipedia articles such as Pluto (Link), there's this number that says how much flattened it is (Definition Here). In Pluto, it's >1%.
Haumea, which is a very flattened dwarf planet, actually doesn't have this information on Wikipedia, and I haven't been able to find it online.
It would be great if someone could find this info (and it's source as well), because I can't seem to find it anywhere.
Thanks in advance!