Using the DMI removes the guesswork involved with spotting trends and can also provide confirmation of trends identified by trendline by analysis. The DMI system is comprised of the ADX (average directional movement index) and the DI+ and DI- lines.The ADX is used to determine whether or not a market is trending (regardless if it's up or down), with a reading over 25 indicating a trending market and a reading below 20 indicating no trend. The ADX is also a measure of the strength of a trend--the higher the ADX, the stronger the trend. Using the ADX, traders can determine whether or not there is a trend and thus whether or not to use a trend following system
