It would be very interesting to see any hard data and their sources for the above study. According to the data in Soros' Alchemy of Finance, it seems to me, as my calculations based on estimated daily volatility might be wrong, roughly he did apply the 2% rule on each market of his investment/ speculation portfolio, probably for diversification purpose.
That's kind of funny... NONE of my trades lose money, ever....except when I'm not on top of my game, blah blah blah m
Less than half percent ... Less than 0.5 percent would be $100 per $20,000. You'd have a cushion if (or when) you have a losing streak. Always, always protect your capital. Risking half a percent will allow you to stay around to see if your trading system really works.