Wells Wilder developed the ADX, and outlined it in his classic book ?New Concepts in Technical Trading Systems?.

Let's look at this essential indicator in more detail - and see how to apply it on your forex charts, to give you greater accuracy when generating your trading signals.

Determining the Strength of the Trend

The ADX is a momentum indicator, which aims to measure the strength of the trend - and attempts to determine if the market is trending, or is trading sideways.

The Advantages of the ADX

A core belief of technical analysis is that a strong trend in motion is more likely to continue, than reverse. Therefore, you always want to be trading strong trends - as your odds of success are higher. The Average Directional Movement is a good indictor ? and you should consider using it as part of your currency trading system.

The Technical Bit

For the boffin's out there, here's the technical bit ? don't worry if you don't understand the calculation, its easy to use when visually plotted. The ADX is based on the comparison of two other directional indicators, both of which were also developed by Wilder, and they are:

Positive Directional Indicator (+DI) and the Negative Directional Indicator (-DI) to produce ADX as showed in the following formula:

ADX = SUM[(+DI-(-DI))/(+DI+(-DI)), N]/N

Where:

N: Refers to the period of calculation. The formula above produces the ADX line, which oscillates between 0 to 100 values. The +DI and -DI are both present and can be seen to make up the indicator.

You don't need to understand the above calculation to use the indicator ? you only need to accept that the indicator works.

The indicator is easy to use when it's visually plotted - and you'll find it included, with most of the good forex chart services.

How to Trade using the ADX Indicator

The ADX it's not a bullish, bearish trading signal generator - and should never be used as such.

The ADX indicator simply indicates the strength of the trend - and other indicators should be used to enter, and exit trades.

Although the ADX fluctuates from 0 to 100, it rarely moves above 60.

Use the ADX in the following way:

Readings above 40 indicate the strength of the trend.

Readings below 20 indicate range trading and flat periods of consolidation.

You can use the crossing of +DI and -DI to determine the trend direction; when +DI crosses -DI upward, it's a bullish signal, on the other hand, when +DI crosses -DI downward it's a bearish signal.

The ADX line is a great momentum indicator and like the RSI (also developed by Wells Wilder), the ADX it will help you trade the strongest trends - and give you advance warning of changes in momentum.

The Bottom Line

If you want currency trading success, you can't just trade support and resistance levels, and hope they hold or break. You need confirmation of momentum to get the odds on your side - and the ADX indicator will assist you.

Final Words

New Concepts in Technical Trading Systems was published in 1978, and was one of the first trading books I ever bought. Every trader should make this book a part of his or her forex education. If you want to learn forex trading the right way, get the book, and use the ADX indicator to increase your chances of making big FX Profits.