The profit potential of a triangle breakout is normally determined by subtracting the low of the triangle from the high and adding that to the breakout point. Triangles are one of those formations that are easier to spot on a chart than they are to program, but I attempted it two different ways.
I first looked at formations where the most recent swing low was higher than the previous swing low and the most recent swing high was lower than the previous swing high. A breakout was defined as a move outside the nearest swing high or low. The profit target was defined as the distance from the entry point plus (or minus for shorts) the highest swing high minus the lowest swing low. A “failure” was defined as a reversal through the opposite swing point in the triangle.
The second way I defined a triangle was a bit simpler. I looked at weekly bars and defined any two consecutive “inside bars” as a triangle. Here again I set a profit target using the biggest bar and defined a stop point as a move through the opposite end of the most recent inside bar.
In both cases the success rates were highly disappointing. Looking at all S&P 100 stocks over the last 15 years, method 1 posted a success rate of about 38% and method 2 a success rate of 30%. The success rate in the S&P 500 Index over the last 30 years was 30% for method 1 and 27% for method 2.
Some traders may still be tempted to play the breakout because the potential reward is higher than the risk. Even so, method 1 was only slightly profitable as gains outsized losses by a mere 1.03 to 1 without factoring in commissions or slippage. Method 2 showed net losses.
It seems to me that the best way to trade these kind of triangle formations is not to play the breakout. Since about 2/3 of the breakouts I tested eventually failed, I’d rather wait for the breakout to occur and then evaluate possible reversal areas that could offer a more substantial edge.