Advance / Decline Line Breadth is a good technical indicator used in forex technical analysis. This indicator can indicates the number of advancing issues divided by the sum number of declining and advancing issues.

The most important prerequisite for the indicators, including the accumulation (distribution) Line, the volume of the price. Volume shows the number of shares traded in a particular stock. Therefore, it is a direct correlation in the capitals move within and outside the camp. It is time the increased volume before moving in many cases a camp progress.

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From ForexRealm
This indicator is the oldest one in the sphere of technical analysis. The Advance/Decline Line – Breadth – indicates the number of advancing issues divided by the sum number of declining and advancing issues.
The market is supposed to be strong or “having good breadth” when advancing issues overcome declining issues. If the line breaks out to the upside one can predict the market increase during upcoming months. And new index peaks have tended to result in the market highs.
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