Maria, what if one were to begin with a much lower investment of say 10 BTC?
She is talking USD, not BTC.
If you want a increase your USD holdings by 20% per month, I suggest buying and holding BTC. The longer you hold, the less likely you are going to lose everything in a dip (assuming BTC is here to stay, that is). Back in 2011 when this thread was started, I would not have been so confident giving the same advice.
PS: I now know the answer to my question in post #224: buy Bitcoin. My bank at the time (that I am slowly moving away from) turned out to be Bitcoin hostile.