Dow and Hamilton identified three types of price movements for the Dow Jones Industrial and Rail averages: primary movements, secondary movements and daily fluctuations. Primary moves last from a few months to many years and represent the broad underlying trend of the market. Secondary (or reaction) movements last from a few weeks to a few months and move counter to the primary trend. Daily fluctuations can move with or against the primary trend and last from a few hours to a few days, but usually not more than a week.

Even though the theory is not meant for short-term trading, it can still add value for traders. No matter what your time frame, it always helps to be able to identify the primary trend. According to Hamilton (writing in the early part of the 20th century), those who successfully applied the Dow theory rarely traded more than four or five times a year. Remember that intraday, day-to-day and possibly even secondary movements can be prone to manipulation, but the primary trend is immune from manipulation. Hamilton and Dow sought a means to filter out the noise associated with daily fluctuations. They were not worried about a couple of points, or getting the exact top or bottom. Their main concern was catching the large moves. Both Hamilton and Dow recommended close study of the markets on a daily basis, but they also sought to minimize the effects of random movements and concentrate on the primary trend. It is easy to get caught up in the madness of the moment and forget the primary trend.

Primary movements represent the broad underlying trend of the market and can last from a few months to many years. These movements are typically referred to as bull and bear markets. Once the primary trend has been identified, it will remain in effect until proved otherwise. (We will address the methods for identifying the primary trend in Part 3 of this Dow Theory article.) Hamilton believed that the length and the duration of the trend were largely indeterminable. Hamilton did study the averages and came up with some general guidelines for length and duration, but warned against attempting to apply these as rules for forecasting.

Many traders and investors get hung up on price and time targets. The reality of the situation is that nobody knows where and when the primary trend will end. The objective of Dow theory is to utilize what we do know, not to haphazardly guess about what we don't know. Through a set of guidelines, Dow theory enables investors to identify the primary trend and invest accordingly. Trying to predict the length and the duration of the trend is an exercise in futility. Hamilton and Dow were mainly interested in catching the big moves of the primary trend. Success, according to Hamilton and Dow, is measured by the ability to identify the primary trend and stay with it.

Secondary movements run counter to the primary trend and are reactionary in nature. In a bull market a secondary move is considered a correction. In a bear market, secondary moves are sometimes called reaction rallies. Hamilton noted some characteristics that were common to many secondary moves in both bull and bear markets. These characteristics should not be construed as rules, but rather as loose guidelines to be used in conjunction with other analysis techniques. The first three characteristics have been applied to the example above.

1.  Based on historical observation, Hamilton estimated that secondary movements retrace 1/3 to 2/3 of the primary move, with 50% being the typical amount. In actuality, the secondary move in early 1997 retraced about 42% of the primary move. (7158 - 5170 = 1988; 7158 - 6316 = 842, 842/1988 = 42.35%).

2.  Hamilton also noted that secondary moves tend to be faster and sharper than the preceding primary move. Just with a visual comparison, we can see that the secondary move was sharper that the preceding primary advance. The primary move advanced 38% (1988/5170 = 38%) and lasted from Jul-96 to Mar-97, about 8 months. The secondary move witnessed a correction of 11.7% (842/7158 = 11.7%) and lasted a mere five weeks.

3.  At the end of the secondary move, there is usually a dull period just before the turnaround. Little price movement, a decline in volume, or a combination of the two can mark this dullness. Below is a daily chart focusing on the Apr-97 low for the secondary move outlined above.

4.  Lows are sometimes accompanied by a high-volume washout day. Although these high-volume lows are not a signal in and of themselves, they help to form a pattern that precedes a significant advance.