Lesson 20 – The MACD

In our last lesson we learned about the different ways people trade with moving averages. In this lesson we are going to learn about the Moving Average Convergence Divergence (MACD) an indicator that is built using moving averages, but is set up to give a good indication of the momentum of a particular financial instrument as well as its trend.

The indicator, which was developed by Gerald Appel, is constructed by taking a 12 period exponential moving average of a financial instrument and subtracting its 26 period exponential moving average. The resulting line is then plotted below the price chart and fluctuates above and below a center line which is placed at value zero. A 9 period EMA of the MACD line is normally plotted along with the MACD line and used as a signal of potential trading opportunities

Example of what a MACD looks like on a chart:

When the MACD line is above zero this tells the trader that the 12 period exponential moving average is trading above the 26 period exponential moving averages. When the MACD line is below zero this tells the trader that the 12 period exponential moving average is below the 26 period exponential moving average. Traders will watch the MACD line as when it is above zero and rising this is a sign that the positive gap between the 12 and 26 EMA’s is widening, a sign of increasing bullish momentum in the financial instrument they are analyzing. Conversely when the MACD line is below zero and falling this represents a widening in the negative gap between the 12 and 26 day EMA’s, a sign of increasing bearish momentum in the financial instrument
they are analyzing.

Example of Rising and Falling MACD lines:

The purpose of the 9 period exponential moving average line is to further confirm bullish changes in momentum when the MACD crosses above this line and bearish changes in momentum when the MACD crosses below this line.

Example of the Signal Line

Lastly many traders and charting packages will plot a histogram along with the MACD which is representative of the distance between the MACD and its signal line. When the MACD histogram is above zero (the MACD line is above the signal line) this is an indication that positive momentum is increasing. Conversely when the MACD histogram is below zero this is an indication that negative momentum is increasing.

Example of the MACD histogram

When the MACD histogram is above zero (the MACD line is above the signal line) this is an indication that positive momentum is increasing. Conversely when the MACD histogram is below zero this is an indication that negative momentum is increasing. The higher or lower the histogram goes above or below zero the greater the momentum of the trend is thought to be.