Declining-Advancing-Issues is a market momentum indicator used to demonstrate the distinction between declining issues and advancing issues on the Exchanges such as NYSE and NASDAQ. This information is used every day to define the market situation.
This is the main formula for many market breadth indicators, including the Absolute Breadth Index, Breadth Thrust, Advance/Decline Line, Advance/Decline Ratio, Summation Index, and McClellan Oscillator. The calculation for the Advancing-Declining Issues is rather easy: Advancing Issues - Declining Issues. Indicators working with declining and advancing issues in the calculations are called market breadth indicators.
This indicator is rather useful for defining daily market strength. Strong "upward days" sometimes have readings over +1,000. Weak "downward days" sometimes have readings below -1,000.