As you can see, the drop resumed after the price made a breakout to the bottom. To trade this chart pattern, we’d put a short order at the bottom of the pennant with a stop loss above the pennant. That way, we’d be out of the trade right away in case the breakdown was a fake out.
Unlike the other chart patterns wherein the size of the next move is approximately the height of the formation, pennants signal much stronger moves. Usually, the height of the earlier move (also known as the mast) is used to estimate the size of the breakout move.