From 1951 - 1991 the avarage S&P growth was 13% per year.
This is the benchmark. The absolute minimum to be achived by any trading.
Well, in USD at least. But let's not compare what 13% today what it would mean in Gold (this year 13% gain is about 1% loss).
From 1997 - 2007, S&P 500 growth was 7.61% on avarage. (-22.1 % in 2002 so fluctuation is very high).