4. What is the Dow Theory?

Dow Theory is one of the earliest and most influential concepts in technical analysis, developed by Charles H. Dow, the founder of the Wall Street Journal and co-founder of Dow Jones & Company. It forms the foundation for understanding market trends and how they evolve over time.

Core Idea of Dow Theory

Dow believed that the stock market moves in predictable phases, and by studying these movements, one can identify major trends and make informed investment decisions.

He laid out six key principles, but the three most practical ideas for traders are:

1. The Market Moves in Trends

There are three types of trends:

Trend TypeDurationExample
Primary TrendLong-term (months/years)Bull or Bear Market
Secondary TrendMedium-term (weeks/months)Corrections or Rallies
Minor TrendShort-term (days/weeks)Daily price fluctuations

Analogy:

2. Market Phases: How Trends Unfold

Each primary trend is broken into three distinct phases:

PhaseDescriptionWhat Happens
AccumulationSmart money enters quietly after a declinePrices move slowly; volume low
Public ParticipationTrend becomes visible to the publicMomentum builds; prices rise sharply
DistributionSmart money exits while retail investors enterPrices flatten or decline on high volume

Example:
After a crash, large institutions start buying during accumulation. As prices rise and news turns positive, the public joins in. Eventually, smart investors sell during distribution, anticipating a reversal.

3. Indices Must Confirm Each Other

Originally based on Dow Jones Industrial Average (DJIA) and Dow Jones Transportation Average (DJTA), Dow believed that:

"No trend is confirmed unless multiple indices show the same direction."

Today’s Interpretation:

Other Key Dow Theory Principles
Key Takeaways