Price Breakout Up: Price fails to gain at least 5% from breakout only 9% of the time; the average maximum gain before any 20% decline is 31%.
Price Breakout Down: Price fails to gain at least 5% from breakout 13% of the time; the average maximum gain from shorting before any 20% reversal upwards is 17%.
Generally technical analysts suggest taking the height of the pattern and then adding or subtracting that from the breakout price (Rockefeller, 2011, p. 165). However, noted chart pattern researcher, Bulkowski (2008) suggests the following breakout price targets for the symmetrical triangle:
Symmetrical Triangle Breakout Upward:
Breakout Price + ((Highest Price in Triangle - Lowest Price in Triangle) * 66%)
Symmetrical Triangle Breakout Downward:
Breakout Price - ((Highest Price in Triangle - Lowest Price in Triangle) * 48%)
A breakout occurs 3/4 of the way into the triangle."