Speaking purely from experience because I don't know the exact percentages, but basically from about 5% to I'd say low 30%s work on Fox and Falco with a single jump. When you start getting to the high 30s to about 60% is when you need to start double jumping to get the rest. Anything above that is either DI dependent or at too high of a percent to even get it without following it up with something else. (Usually Pound if they DI hard right or left, but getting it off Pound is also DI dependent.)
If you start at 0% on spacies though then it's best to go for up-throw -> Up-air -> Up-throw -> rest.
If you get lucky with bad DI against Falcons you can also get up-throw rest on them, but that's very, very unlikely. I've only managed to get it once or twice because they're normally able to either jump out or just know to DI.