What Is an Average Directional Index (ADX)?
An Average Directional Index (ADX) is a technical indicator used to measure the strength of a trend. It was developed by J. Welles Wilder and introduced in his 1978 book, New Concepts in Technical Trading Systems. The ADX measures the strength of a trend based on its direction and range over time. It does not indicate whether the trend is up or down; instead, it simply indicates how strong the current trend is relative to past trends.
The ADX calculation involves three components: +DI (positive directional index), -DI (negative directional index), and an average of these two values called DX (directional movement). The +DI line measures upward momentum while the -DI line measures downward momentum. When both lines are rising together, this suggests that there is strong buying pressure pushing prices higher; when they are falling together, this suggests that there is strong selling pressure pushing prices lower. A reading above 25 usually signals that a new trend has begun while readings below 20 suggest that price action may be ranging rather than trending strongly in either direction.
How to Calculate the Average Directional Index (ADX)
The Average Directional Index (ADX) is a technical indicator used to measure the strength of a trend. It can be used to determine whether an asset is trending or not, and if so, how strong the trend is. The ADX calculation involves taking two moving averages of price data and then subtracting them from each other. This difference between the two moving averages gives us an indication of how strong the current trend in price action is.
To calculate ADX, first you need to find out what period you want your moving average calculations for – typically 14 periods are used as this provides enough information without being too noisy. Then take two exponential moving averages (EMAs), one with a shorter time frame than the other; usually 9-period EMA and 26-period EMA are chosen for this purpose. Subtract these EMAs from each other and multiply by 100; this will give you your ADX value which ranges from 0 to 100 where higher values indicate stronger trends while lower values indicate weaker trends or no trend at all.