Way back when, I did a survey of money manager performance... all kinds... equities, mutual funds, futures, etc... with 10-year, AUDITED results.
30%, average compounded return... 0.1% of managers.
40%, average compounded return... you could count them on your fingers.
However, I believe "20%/yr = par" for disciplined, technical traders.... regardless of which markets they play.
Years ago trading mutual fund accounts, I averaged 41%/yr for 18 years... and I even had a 5-year period where I averaged 75%/yr, compounded... That was before there were leveraged and inverse funds, so I know it's "do-able".
Bottom line... (1) be protective of your capital, and (2) shoot for a "conservative 20%/yr".... and you might do even better.... but if you're going to make an error, make it on the "preserve capital" side.