In technical analysis, a head and shoulders pattern describes a specific chart formation that predicts a bullish-to-bearish trend reversal. The head and shoulders pattern is believed to be one of the most reliable trend reversal patterns. It is one of several top patterns that signal, with varying degrees of accuracy, that an upward trend is nearing its end.
This pattern is comprised of three component parts:
1. After a long bullish trends, the price rises to a peak and subsequently declines to form a trough.
2. The price rises again to form a second high substantially above the initial peak and declines again.
3. The price rises a third time, but only to the level of the first peak, before declining once more.
The first and third peaks are shoulders, and the second peak forms the head. The line connecting the first and second troughs is called the neckline.
Head and shoulders patterns can also signal that a downward trend is about to reverse into an upward trend. In this case, the stocks price reaches three consecutive lows, separated by temporary rallies. Of these, the second trough is the lowest (the head) and the first and third are slightly shallower (the shoulders). The final rally after the third dip signals that the bearish trend has reversed and prices are likely to keep moving up.
Stock prices are the result of a continuous game of tug-of-war; whether a stock's price goes up or down is the direct result of how many people are on each team. Those who believe a stock's price will go up are called bulls, and those who believe the stock will go down are called bears. If more of a stock's shareholders are bears, then its price will go down as they sell their shares to avoid losing money. If more people are bullish, then the price will go up as new investors buy in to take advantage of the opportunity.
Like all charting patterns, the ups and downs of the head and shoulders pattern tell a very specific story about the battle being waged between bulls and bears.
The initial peak and subsequent decline represent the waning momentum of the prior bullish trend. Wanting to sustain the upward movement as long as possible, bulls rally to push the price back up past the initial peak to reach a new high (the head). At this point, it is still possible that bulls could reinstate their market dominance and continue the upward trend.
However, once price declines a second time and reaches a point below the initial peak, it is clear that bears are gaining ground. Bulls try one more time to push price upward, but succeed only in hitting the lesser high reached in the initial peak. This failure to surpass the highest high signals the bulls' defeat and bears take over, driving the price downward and completing the reversal.